Programmable discrete digital receiver components

ABSTRACT

A receiver includes a sample and hold module, a discrete time filter module, and a conversion module. The sample and hold module includes a sample switching module, an impedance module, and a hold switching module. The sample switching module outputs samples of an inbound wireless signal in accordance with a sampling clock signal. The impedance module temporarily stores the samples. The hold switching module outputs a filtered representation of the samples in accordance with a hold clock signal to produce a frequency domain sample pulse train, wherein a filter response of the sample and hold module is in accordance with a ratio between the sampling clock signal and the hold clock signal. The discrete time filter module, which may be programmable, filters the frequency domain sample pulse train. The conversion module, which may be programmable, converts the filtered sample pulse into an inbound baseband signal.

CROSS REFERENCE TO RELATED PATENTS

This patent application is claiming priority under 35 USC §120 as acontinuing patent application of co-pending patent application entitledDISCRETE DIGITAL RECEIVER, having a filing date of Sep. 22, 2011, and aSer. No. 13/240,639 (Attorney Docket Number BP23555), which isincorporated herein by reference and which claims priority under 35 USC§119(e) to a provisionally filed patent application entitled DISCRETEDIGITAL RF TRANSCEIVER, having a provisional filing date of Jul. 31,2011, and a provisional Ser. No. 61/513,627 (Attorney Docket NumberBP23021), which is incorporated by reference herein.

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

NOT APPLICABLE

INCORPORATION-BY-REFERENCE OF MATERIAL SUBMITTED ON A COMPACT DISC

NOT APPLICABLE

BACKGROUND OF THE INVENTION

1. Technical Field of the Invention

This invention relates generally to wireless communication systems andmore particularly to wireless communication devices.

2. Description of Related Art

Communication systems are known to support wireless and wire linedcommunications between wireless and/or wire lined communication devices.Such communication systems range from national and/or internationalcellular telephone systems to the Internet to point-to-point in-homewireless networks. Each type of communication system is constructed, andhence operates, in accordance with one or more communication standards.For instance, wireless communication systems may operate in accordancewith one or more standards including, but not limited to, IEEE 802.11,Bluetooth, advanced mobile phone services (AMPS), digital AMPS, globalsystem for mobile communications (GSM), code division multiple access(CDMA), local multi-point distribution systems (LMDS),multi-channel-multi-point distribution systems (MMDS), radio frequencyidentification (RFID), Enhanced Data rates for GSM Evolution (EDGE),General Packet Radio Service (GPRS), WCDMA, LTE (Long Term Evolution),WiMAX (worldwide interoperability for microwave access), and/orvariations thereof.

Depending on the type of wireless communication system, a wirelesscommunication device, such as a cellular telephone, two-way radio,personal digital assistant (PDA), personal computer (PC), laptopcomputer, home entertainment equipment, RFID reader, RFID tag, et ceteracommunicates directly or indirectly with other wireless communicationdevices. For direct communications (also known as point-to-pointcommunications), the participating wireless communication devices tunetheir receivers and transmitters to the same channel or channels (e.g.,one of the plurality of radio frequency (RF) carriers of the wirelesscommunication system or a particular RF frequency for some systems) andcommunicate over that channel(s). For indirect wireless communications,each wireless communication device communicates directly with anassociated base station (e.g., for cellular services) and/or anassociated access point (e.g., for an in-home or in-building wirelessnetwork) via an assigned channel. To complete a communication connectionbetween the wireless communication devices, the associated base stationsand/or associated access points communicate with each other directly,via a system controller, via the public switch telephone network, viathe Internet, and/or via some other wide area network.

For each wireless communication device to participate in wirelesscommunications, it includes a built-in radio transceiver (i.e., receiverand transmitter) or is coupled to an associated radio transceiver (e.g.,a station for in-home and/or in-building wireless communicationnetworks, RF modem, etc.). As is known, the receiver is coupled to anantenna and includes a low noise amplifier, one or more intermediatefrequency stages, a filtering stage, and a data recovery stage. The lownoise amplifier receives inbound RF signals via the antenna andamplifies then. The one or more intermediate frequency stages mix theamplified RF signals with one or more local oscillations to convert theamplified RF signal into baseband signals or intermediate frequency (IF)signals. The filtering stage filters the baseband signals or the IFsignals to attenuate unwanted out of band signals to produce filteredsignals. The data recovery stage recovers data from the filtered signalsin accordance with the particular wireless communication standard.

As is also known, the transmitter includes a data modulation stage, oneor more intermediate frequency stages, and a power amplifier. The datamodulation stage converts data into baseband signals in accordance witha particular wireless communication standard. The one or moreintermediate frequency stages mix the baseband signals with one or morelocal oscillations to produce RF signals. The power amplifier amplifiesthe RF signals prior to transmission via an antenna.

To implement a radio transceiver, a wireless communication deviceincludes a plurality of integrated circuits (ICs) and a plurality ofdiscrete components. For example, a wireless communication device thatsupports 2G and 3G cellular telephone protocols includes a basebandprocessing IC, a power management IC, a radio transceiver IC, atransmit/receive (T/R) switch, an antenna, and a plurality of discretecomponents. The discrete components include surface acoustic wave (SAW)filters, power amplifiers, duplexers, inductors, and capacitors. Suchdiscrete components add several dollars (US) to the bill of material forthe wireless communication device, but are necessary to achieve thestrict performance requirements of the 2G and 3G protocols.

As integrated circuit fabrication technology evolves, wirelesscommunication device manufacturers require that wireless transceiver ICmanufacturers update their ICs in accordance with the advancements in ICfabrication. For example, as the fabrication process changes (e.g., usessmaller transistor sizes), the wireless transceiver ICs are redesignedfor the newer fabrication process. Redesigning the digital portions ofthe ICs is a relatively straightforward process since most digitalcircuitry “shrinks” with the IC fabrication process. Redesigning theanalog portions, however, is not a straightforward task since mostanalog circuitry (e.g., inductors, capacitors, etc.) does not “shrink”with the IC process. As such, wireless transceiver IC manufacturersinvest significant effort to produce ICs of newer IC fabricationprocesses.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING(S)

FIG. 1 is a schematic block diagram of an embodiment of a wirelesstransceiver in accordance with the present invention;

FIG. 2 is a schematic block diagram of an embodiment of a multiple inputmultiple output (MIMO) wireless transceiver in accordance with thepresent invention;

FIG. 3 is a schematic block diagram of an embodiment of a multiplefrequency band wireless transceiver in accordance with the presentinvention;

FIG. 4 is a schematic block diagram of an embodiment of a receiver ofone or more of the transceivers of FIGS. 1-3 in accordance with thepresent invention;

FIG. 5 is a diagram of an example of operation of an RF bandpass filterand low noise amplifier of the receiver of FIG. 4 in accordance with thepresent invention;

FIG. 6 is a diagram of an example of operation of a sample and holdfilter circuit of the receiver of FIG. 4 in accordance with the presentinvention;

FIG. 7 is a diagram of an example of an input signal, in the timedomain, of a sample and hold filter circuit in accordance with thepresent invention;

FIG. 8 is a diagram of an example of the inbound signal, in thefrequency domain, of the sample and hold filter circuit in accordancewith the present invention;

FIG. 9 is a diagram of an example of sampling the inbound signal, in thetime domain, at a given sampling period (T_(s)) in accordance with thepresent invention;

FIG. 10 is a diagram of an example of a sampled inbound signal, in thefrequency domain, at a sampling frequency (f_(s)) in accordance with thepresent invention;

FIG. 11 is a diagram of an example of sampling and holding the inboundsignal, in the time domain, at a given sampling period (T_(s)) andholding period (T_(h)) in accordance with the present invention;

FIG. 12 is a diagram of an example of a sampled and held inbound signal,in the frequency domain, with various ratios of T_(s)-to-T_(h) inaccordance with the present invention;

FIG. 13 is a diagram of an example of the inbound RF signal, in thefrequency domain, of the receiver of FIG. 4 in accordance with thepresent invention;

FIG. 14 is a diagram of an example of the inbound RF signal, in thefrequency domain, of the sample and hold filter circuit in accordancewith the present invention;

FIG. 15 is a diagram of an example of a sampled inbound RF signal, inthe frequency domain, at a sampling frequency (f_(s)) in accordance withthe present invention;

FIG. 16 is a diagram of an example of bandpass filtering of the samplingand hold filter circuit of the sampled inbound RF signal, in thefrequency domain, at a sampling frequency (f_(s)) in accordance with thepresent invention;

FIG. 17 is a diagram of another example of bandpass filtering of thesampling and hold filter circuit of the sampled inbound RF signal, inthe frequency domain, at a sampling frequency (f_(s)) in accordance withthe present invention;

FIG. 18 is a diagram of another example of bandpass filtering of thesampling and hold filter circuit of the sampled inbound RF signal, inthe frequency domain, at a sampling frequency (f_(s)) in accordance withthe present invention;

FIG. 19 is a schematic block diagram of an embodiment of a sample andhold filter circuit in accordance with the present invention;

FIG. 20 is a schematic block diagram of another embodiment of a sampleand hold filter circuit in accordance with the present invention;

FIG. 21 is a schematic block diagram of an embodiment of an impedanceelement of a sample and hold filter circuit in accordance with thepresent invention;

FIG. 22 is a schematic block diagram of another embodiment of animpedance element of a sample and hold filter circuit in accordance withthe present invention;

FIG. 23 is a schematic block diagram of another embodiment of a sampleand hold filter circuit in accordance with the present invention;

FIG. 24 is a schematic block diagram of another embodiment of a sampleand hold filter circuit in accordance with the present invention;

FIG. 25 is a schematic block diagram of an embodiment of an impedancecircuit of a sample and hold filter circuit in accordance with thepresent invention;

FIG. 26 is a schematic block diagram of another embodiment of animpedance circuit of a sample and hold filter circuit in accordance withthe present invention;

FIG. 27 is a diagram of another example of bandpass filtering of thesampling and hold filter circuit with an RF tuned impedance circuit inaccordance with the present invention;

FIG. 28 is a diagram of another example of bandpass filtering of thesampling and hold filter circuit with an f_(s) tuned impedance circuitin accordance with the present invention;

FIG. 29 is a diagram of another example of bandpass filtering of thesampling and hold filter circuit with a baseband tuned impedance circuitin accordance with the present invention;

FIG. 30 is a schematic block diagram of an embodiment of a sample andhold clock generator circuit in accordance with the present invention;

FIG. 31 is a diagram of an example of phase offset clock signalsproduced by the sample and hold clock generator circuit in accordancewith the present invention;

FIG. 32 is a diagram of an example of a sample clock signal and a holdclock signal produced by the sample and hold clock generator circuit inaccordance with the present invention;

FIG. 33 is a schematic block diagram of an embodiment of a programmablediscrete time filter in accordance with the present invention;

FIG. 34 is a schematic block diagram of another embodiment of aprogrammable discrete time filter in accordance with the presentinvention;

FIG. 35 is a schematic block diagram of an embodiment of a frequencytranslation band pass filter (FTBPF) in accordance with the presentinvention;

FIG. 36 is a schematic block diagram of an embodiment of a filter clockgenerating circuit in accordance with the present invention;

FIG. 37 is a diagram of an example of frequency translation of a bandpass filter in accordance with the present invention;

FIG. 38 is a schematic block diagram of another embodiment of a receiverof one or more of the transceivers of FIGS. 1-3 in accordance with thepresent invention;

FIG. 39 is a schematic block diagram of another embodiment of a receiverof one or more of the transceivers of FIGS. 1-3 in accordance with thepresent invention;

FIG. 40 is a schematic block diagram of an embodiment of an analog todigital converter within a receiver of one or more of the transceiversof FIGS. 1-3 in accordance with the present invention;

FIG. 41 is a schematic block diagram of another embodiment of a receiverof one or more of the transceivers of FIGS. 1-3 in accordance with thepresent invention;

FIG. 42 is a schematic block diagram of another embodiment of a receiverof one or more of the transceivers of FIGS. 1-3 in accordance with thepresent invention;

FIG. 43 is a diagram of an example of a time domain and a frequencydomain representation of an output of the LNA of the receiver of FIG. 42in accordance with the present invention;

FIG. 44 is a diagram of an example of a frequency domain representationof an output of the sample and hold filter circuit of the receiver ofFIG. 42 in accordance with the present invention;

FIG. 45 is a diagram of an example of a frequency domain representationof an output of the discrete time filter of the receiver of FIG. 42 inaccordance with the present invention;

FIG. 46 is a schematic block diagram of another embodiment of a receiverof one or more of the transceivers of FIGS. 1-3 in accordance with thepresent invention;

FIG. 47 is a schematic block diagram of another embodiment of a receiverof one or more of the transceivers of FIGS. 1-3 in accordance with thepresent invention;

FIG. 48 is a diagram of an example of a time domain and a frequencydomain representation of an output of the LNA of the receiver of FIG. 47in accordance with the present invention;

FIG. 49 is a diagram of an example of a frequency domain representationof an output of the sample and hold filter circuit of the receiver ofFIG. 47 in accordance with the present invention;

FIG. 50 is a diagram of an example of a frequency domain representationof an output of the discrete time filter of the receiver of FIG. 47 inaccordance with the present invention;

FIG. 51 is a diagram of an example of a frequency domain representationof an output of the down conversion module of the receiver of FIG. 47 inaccordance with the present invention;

FIG. 52 is a schematic block diagram of another embodiment of a receiverof one or more of the transceivers of FIGS. 1-3 in accordance with thepresent invention;

FIG. 53 is a diagram of an example of a frequency domain representationof an output of the sample and hold filter circuit of the receiver ofFIG. 52 in accordance with the present invention;

FIG. 54 is a diagram of an example of a frequency domain representationof an output of the discrete time filter of the receiver of FIG. 52 inaccordance with the present invention;

FIG. 55 is a diagram of an example of a frequency domain representationof an output of a sample and hold circuit of a down conversion module ofthe receiver of FIG. 52 in accordance with the present invention;

FIG. 56 is a diagram of an example of a frequency domain representationof an output of a discrete time filter circuit of the down conversionmodule of the receiver of FIG. 52 in accordance with the presentinvention;

FIG. 57 is a schematic block diagram of another embodiment of a receiverof one or more of the transceivers of FIGS. 1-3 in accordance with thepresent invention;

FIG. 58 is a diagram of an example of a frequency domain representationof an output of the sample and hold filter circuit of the receiver ofFIG. 57 in accordance with the present invention;

FIG. 59 is a diagram of an example of a frequency domain representationof an output of the discrete time filter of the receiver of FIG. 57 inaccordance with the present invention;

FIG. 60 is a diagram of an example of a frequency domain representationof an output of a sample and hold circuit of a down conversion module ofthe receiver of FIG. 57 in accordance with the present invention;

FIG. 61 is a diagram of an example of a frequency domain representationof an output of a discrete time filter circuit of the down conversionmodule of the receiver of FIG. 57 in accordance with the presentinvention;

FIG. 62 is a schematic block diagram of another embodiment of a receiverof one or more of the transceivers of FIGS. 1-3 in accordance with thepresent invention;

FIG. 63 is a diagram of an example of a frequency domain representationof an input and an output of a forward path sample and hold filtercircuit of the receiver of FIG. 62 in accordance with the presentinvention;

FIG. 64 is a diagram of an example of a frequency domain representationof an output of a forward path discrete time filter of the receiver ofFIG. 62 in accordance with the present invention;

FIG. 65 is a diagram of an example of a frequency domain representationof an output of a blocker path sample and hold filter circuit of thereceiver of FIG. 62 in accordance with the present invention;

FIG. 66 is a diagram of an example of a frequency domain representationof an output of a blocker path discrete time filter of the receiver ofFIG. 62 in accordance with the present invention;

FIG. 67 is a schematic block diagram of another embodiment of a receiverof one or more of the transceivers of FIGS. 1-3 in accordance with thepresent invention;

FIG. 68 is a schematic block diagram of another embodiment of a receiverof one or more of the transceivers of FIGS. 1-3 in accordance with thepresent invention;

FIG. 69 is a diagram of an example of a frequency domain representationof an output of the LNA of the receiver of FIG. 68 in accordance withthe present invention;

FIG. 70 is a diagram of an example of a frequency domain representationof an output of the sample and hold filter circuit of the receiver ofFIG. 68 in accordance with the present invention;

FIG. 71 is a diagram of an example of a frequency domain representationof an output of an RF path discrete time filter of the receiver of FIG.68 in accordance with the present invention;

FIG. 72 is a diagram of an example of a frequency domain representationof an output of an IF path discrete time filter of the receiver of FIG.68 in accordance with the present invention;

FIG. 73 is a schematic block diagram of another embodiment of a receiverof one or more of the transceivers of FIGS. 1-3 in accordance with thepresent invention;

FIG. 74 is a diagram of an example of a frequency domain representationof an output of the LNA of the receiver of FIG. 68 in accordance withthe present invention;

FIG. 75 is a diagram of an example of a frequency domain representationof an output of the sample and hold filter circuit of the receiver ofFIG. 68 in accordance with the present invention;

FIG. 76 is a diagram of an example of a frequency domain representationof an output of an RF path discrete time filter of the receiver of FIG.68 in accordance with the present invention;

FIG. 77 is a diagram of an example of a frequency domain representationof an output of an IF path discrete time filter of the receiver of FIG.68 in accordance with the present invention;

FIG. 78 is a schematic block diagram of another embodiment of a receiverof one or more of the transceivers of FIGS. 1-3 in accordance with thepresent invention;

FIG. 79 is a schematic block diagram of another embodiment of a receiverof one or more of the transceivers of FIGS. 1-3 in accordance with thepresent invention;

FIG. 80 is a schematic block diagram of another embodiment of a receiverof one or more of the transceivers of FIGS. 1-3 in accordance with thepresent invention;

FIG. 81 is a schematic block diagram of another embodiment of a receiverof one or more of the transceivers of FIGS. 1-3 in accordance with thepresent invention;

FIG. 82 is a schematic block diagram of an embodiment of a programmablefront end of a receiver of one or more of the transceivers of FIGS. 1-3in accordance with the present invention;

FIG. 83 is a schematic block diagram of another embodiment of a receiverof one or more of the transceivers of FIGS. 1-3 in accordance with thepresent invention;

FIG. 84 is a schematic block diagram of an embodiment of sample memoryof the receiver of FIG. 83 in accordance with the present invention;

FIG. 85 is a schematic block diagram of another embodiment of samplememory of the receiver of FIG. 83 in accordance with the presentinvention;

FIG. 86 is a diagram of an example of converting bits into outbound RFsignals in accordance with the present invention;

FIG. 87 is a diagram of an example of converting inbound RF signals intobits in accordance with the present invention;

FIG. 88 is a diagram of an example of converting inbound RF signals intobits that includes sample buffering in accordance with the presentinvention;

FIG. 89 is a diagram of an example of converting inbound RF signals intobits that includes error correction processing in accordance with thepresent invention;

FIG. 90 is a logic diagram of an example method of setting, adjusting,and/or calibrating receiver parameters in accordance with the presentinvention;

FIG. 91 is a schematic block diagram of another embodiment of a receiverof one or more of the transceivers of FIGS. 1-3 in accordance with thepresent invention;

FIG. 92 is a diagram of an example of sampling and holding an inboundsignal, in the time domain, at a given sampling period (T_(s)), aholding period (T_(h)), and given phase of the clock signal inaccordance with the present invention;

FIG. 93 is a diagram of another example of sampling and holding aninbound signal, in the time domain, at a given sampling period (T_(s)),a holding period (T_(h)), and another phase of the clock signal inaccordance with the present invention;

FIG. 94 is a diagram of another example of sampling and holding aninbound signal, in the time domain, at a given sampling period (T_(s)),a holding period (T_(h)), and another phase of the clock signal inaccordance with the present invention;

FIG. 95 is a schematic block diagram of another embodiment of a receiverof one or more of the transceivers of FIGS. 1-3 in accordance with thepresent invention;

FIG. 96 is a schematic block diagram of another embodiment of a receiverof one or more of the transceivers of FIGS. 1-3 in accordance with thepresent invention;

FIG. 97 is a schematic block diagram of another embodiment of a receiverof one or more of the transceivers of FIGS. 1-3 in accordance with thepresent invention;

FIG. 98 is a diagram of an example of a frequency domain representationof an input of the sample and hold filter circuit of the receiver ofFIG. 97 in accordance with the present invention;

FIG. 99 is a diagram of an example of a frequency domain representationof an output of the sample and hold filter circuit of the receiver ofFIG. 97 in accordance with the present invention;

FIG. 100 is a diagram of an example of a frequency domain representationof an output of a discrete time filter of the receiver of FIG. 97 inaccordance with the present invention;

FIG. 101 is a schematic block diagram of another embodiment of areceiver of one or more of the transceivers of FIGS. 1-3 in accordancewith the present invention;

FIG. 102 is a diagram of an example of a frequency domain representationof an input of the sample and hold filter circuit of the receiver ofFIG. 101 in accordance with the present invention;

FIG. 103 is a diagram of an example of a frequency domain representationof an output of the sample and hold filter circuit of the receiver ofFIG. 101 in accordance with the present invention;

FIG. 104 is a diagram of an example of a frequency domain representationof an output of a discrete time filter of the receiver of FIG. 101 inaccordance with the present invention;

FIG. 105 is a diagram of an example of a frequency domain representationof another output of a discrete time filter of the receiver of FIG. 101in accordance with the present invention;

FIG. 106 is a diagram of another example of a frequency domainrepresentation of an input of the sample and hold filter circuit of thereceiver of FIG. 101 in accordance with the present invention;

FIG. 107 is a diagram of another example of a frequency domainrepresentation of a first output of the sample and hold filter circuitof the receiver of FIG. 101 in accordance with the present invention;

FIG. 108 is a diagram of another example of a frequency domainrepresentation of a second output of the sample and hold filter circuitof the receiver of FIG. 101 in accordance with the present invention;

FIG. 109 is a schematic block diagram of another embodiment of a sampleand hold circuit in accordance with the present invention;

FIG. 109A is a schematic block diagram of another embodiment of a sampleand hold circuit in accordance with the present invention;

FIG. 110 is a schematic block diagram of another embodiment of a sampleand hold circuit in accordance with the present invention;

FIG. 111 is a schematic block diagram of another embodiment of areceiver of one or more of the transceivers of FIGS. 1-3 in accordancewith the present invention;

FIG. 112 is a diagram of another example of a frequency domainrepresentation of an input of the sample and hold filter circuit of thereceiver of FIG. 111 in accordance with the present invention;

FIG. 113 is a diagram of another example of a frequency domainrepresentation of a first output of the sample and hold filter circuitof the receiver of FIG. 111 in accordance with the present invention;

FIG. 114 is a diagram of another example of a frequency domainrepresentation of a second output of the sample and hold filter circuitof the receiver of FIG. 111 in accordance with the present invention;

FIG. 115 is a schematic block diagram of another embodiment of atransmitter of one or more of the transceivers of FIGS. 1-3 inaccordance with the present invention;

FIG. 116 is a diagram of an example of a frequency domain representationof an input and an output of the sample and hold filter circuit of thetransmitter of FIG. 115 in accordance with the present invention;

FIG. 117 is a diagram of an example of a frequency domain representationof an input and an output of a discrete time filter of the transmitterof FIG. 116 in accordance with the present invention;

FIG. 118 is a schematic block diagram of another embodiment of atransmitter of one or more of the transceivers of FIGS. 1-3 inaccordance with the present invention;

FIG. 119 is a diagram of an example of a frequency domain representationof an input and an output of the sample and hold filter circuit of thetransmitter of FIG. 118 in accordance with the present invention;

FIG. 120 is a diagram of an example of a frequency domain representationof an input and an output of a discrete time filter of the transmitterof FIG. 118 in accordance with the present invention;

FIG. 121 is a schematic block diagram of another embodiment of atransmitter of one or more of the transceivers of FIGS. 1-3 inaccordance with the present invention;

FIG. 122 is a diagram of an example of a frequency domain representationof an input and an output of the sample and hold filter circuit of thetransmitter of FIG. 121 in accordance with the present invention;

FIG. 123 is a diagram of an example of a frequency domain representationof an input and an output of the transmitter of FIG. 121 in accordancewith the present invention;

FIG. 124 is a schematic block diagram of another embodiment of atransmitter of one or more of the transceivers of FIGS. 1-3 inaccordance with the present invention;

FIG. 125 is a diagram of an example of a frequency domain representationof an input and an output of the sample and hold filter circuit of thetransmitter of FIG. 124 in accordance with the present invention;

FIG. 126 is a diagram of an example of a frequency domain representationof an input and an output of a discrete time filter of the transmitterof FIG. 124 in accordance with the present invention;

FIG. 127 is a diagram of another example of a frequency domainrepresentation of an input and an output of the sample and hold filtercircuit of the transmitter of FIG. 124 in accordance with the presentinvention;

FIG. 128 is a diagram of another example of a frequency domainrepresentation of an input and an output of a discrete time filter ofthe transmitter of FIG. 124 in accordance with the present invention;and

FIG. 129 is a schematic block diagram of another embodiment of atransceiver in accordance with the present invention.

DETAILED DESCRIPTION OF THE INVENTION

FIG. 1 is a schematic block diagram of an embodiment of a wirelesstransceiver that includes an antenna assembly 10, an antenna interface12, a transmitter section 14, a clocking circuit module 16, a discretedigital receiver section 18, and a baseband processing module 20. Theantenna assembly 10 may include one or more antennas, one or moreantenna arrays, a diversity antenna structure, one or more separatetransmit antennas, one or more separate receive antennas, and/or acombination thereof. The antenna interface 12 includes one or moreantenna tuning units, one or more transmission lines, one or moreimpedance matching circuits, one or more transformer baluns, one or moretransmit-receive switches, one or more transmit-receive isolationmodules, etc. The wireless transceiver may further include a powermanagement module (not shown).

The wireless transceiver may be included within a portable computingcommunication device, which may be any device that can be carried by aperson, can be at least partially powered by a battery, and/or performsone or more software applications. For example, the portable computingcommunication device may be a cellular telephone, a laptop computer, apersonal digital assistant, a video game console, a video game player, apersonal entertainment unit, a tablet computer, etc. Note that thewireless radio transceiver may operate in the radio frequency (RF)frequency spectrum and/or the millimeter wave (MMW)) frequency spectrum.

In an example of operation, the baseband processing module 20 performsone or more functions of the portable computing communication devicethat require wireless transmission of data. In this instance, thebaseband processing module 20 receives or generates outbound data 22(e.g., voice, text, audio, video, graphics, etc.) and converts it intoone or more outbound symbol streams 24 in accordance with one or morewireless communication standards (e.g., GSM, CDMA, WCDMA, HSUPA, HSDPA,WiMAX, EDGE, GPRS, IEEE 802.11, Bluetooth, ZigBee, universal mobiletelecommunications system (UMTS), long term evolution (LTE), IEEE802.16, evolution data optimized (EV-DO), etc.). Such a conversionincludes one or more of: scrambling, puncturing, encoding, interleaving,constellation mapping, modulation, frequency spreading, frequencyhopping, beamforming, space-time-block encoding, space-frequency-blockencoding, frequency to time domain conversion, and/or digital basebandto intermediate frequency conversion. Note that the baseband processingmodule 20 converts the outbound data 22 into a single outbound symbolstream 24 for Single Input Single Output (SISO) communications and/orfor Multiple Input Single Output (MISO) communications and converts theoutbound data 22 into multiple outbound symbol streams 24 for SingleInput Multiple Output (SIMO) and Multiple Input Multiple Output (MIMO)communications (which will be described further with reference to FIG.2).

The baseband processing module 20 provides the one or more outboundsymbol streams 22 to the transmitter section, which converts theoutbound symbol stream(s) 24 into one or more outbound RF signals 26(e.g., signals in one or more frequency bands 800 MHz, 1800 MHz, 1900MHz, 2000 MHz, 2.4 GHz, 5 GHz, 60 GHz, etc.). The transceiver section 14may be implemented using a discrete digital topology (as will bediscussed in greater detail with reference to one or more of FIGS.115-129) or implemented using analog circuitry (e.g., an up-conversionmodule, analog baseband and/or RF filtering, a power amplifier, etc.).Regardless of the specific implementation, the transmitter section 14may have a direct conversion topology (e.g., direct conversion ofbaseband or near baseband symbol streams to RF signals) or a superheterodyne topology (e.g., convert baseband or near baseband symbolstreams into intermediate frequency (IF) signals and then convert the IFsignals into RF signals).

For a direction conversion, the transmitter section 14 may have aCartesian-based topology, a polar-based topology, or a hybridpolar-Cartesian-based topology. In a Cartesian-based topology, thetransmitter section 14 receives the outbound symbol stream 24 asin-phase (I) and quadrature (Q) components (e.g.,A_(I)(t)cos(ω_(BB)(t)+φ_(I)(t)) and A_(Q)(t)cos(ω_(BB)(t)+φ_(Q)(t),respectively) and converts the outbound symbol stream 24 intoup-converted signals (e.g., A(t)cos(ω_(BB)(t)+φ(t))+ω_(RF)(t))). Forexample, the I and Q components of the outbound symbol stream 24 ismixed with in-phase and quadrature components (e.g., cos(ω_(RF)(t)) andsin(ω_(RF)(t), respectively) of a transmit local oscillation (TX LO) toproduce mixed signals. One or more filters filter the mixed signals toproduce the up-converted signals. As another example, the I and Qcomponents of the outbound symbol stream 24 are up-sampled and filteredto produce the up-converted signals. One or more power amplifiersamplify the outbound up-converted signal(s) to produce an outbound RFsignal(s) 26.

In a phase polar-based topology, the transmitter section 14 receives theoutbound symbol stream 24 in polar coordinates (e.g.,A(t)cos(ω_(BB)(t)+φ(t)) or A(t)cos(ω_(BB)(t)+/−Δφ)). In an example, thetransmitter section 14 includes an oscillator that produces anoscillation (e.g., cos(ω_(RF)(t) that is adjusted based on the phaseinformation (e.g., +/−Δφ [phase shift] and/or φ(t) [phase modulation])of the outbound symbol stream(s) 24. The resulting adjusted oscillation(e.g., cos(ω_(RF)(t)+/−Δφ) or cos(ω_(RF)(t)+φ(t)) may be furtheradjusted by amplitude information (e.g., A(t) [amplitude modulation]) ofthe outbound symbol stream(s) 24 to produce one or more up-convertedsignals (e.g., A(t)cos(ω_(RF)(t)+φ(t)) or A(t)cos(ω_(RF)(t)+/−Δφ)). Inanother example, the polar coordinate based outbound symbol stream isup-sampled and discrete digitally filtered to produce the one or moreup-converted signals. One or more power amplifiers amplify the outboundup-converted signal(s) to produce an outbound RF signal(s) 26.

In a frequency polar-based topology, the transmitter section 14 receivesthe outbound symbol stream 24 in frequency-polar coordinates (e.g.,A(t)cos(ω_(BB)(t)+f(t)) or A(t)cos(ω_(BB)(t)+/−Δf)). In an example, thetransmitter section 14 includes an oscillator that produces anoscillation (e.g., cos(ω_(RF)(t)) this is adjusted based on thefrequency information (e.g., +/−Δf [frequency shift] and/or f(t))[frequency modulation]) of the outbound symbol stream(s) 24. Theresulting adjusted oscillation (e.g., cos(ω_(RF)(t)+/−Δf) orcos(ω_(RF)(t)+f(t)) may be further adjusted by amplitude information(e.g., A(t) [amplitude modulation]) of the outbound symbol stream(s) 24to produce one or more up-converted signals (e.g.,A(t)cos(ω_(RF)(t)+f(t)) or A(t)cos(ω_(RF)(t)+/−Δf)). In another example,the frequency-polar coordinate based outbound symbol stream 24 isup-sampled and discrete digitally filtered to produce the one or moreup-converted signals. One or more power amplifiers amplify the outboundup-converted signal(s) to produce an outbound RF signal(s) 26.

In a hybrid polar-Cartesian-based topology, the transmitter section 14receives the outbound symbol stream 24 as phase information (e.g.,cos(ω_(BB)(t)+/−Δφ) or cos(ω_(BB)(t)+φ(t)) and amplitude information(e.g., A(t)). In an example, the transmitter section 14 mixes in-phaseand quadrature components (e.g., cos(ω_(BB)(t)+φ_(I)(t)) andcos(ω_(BB)(t)+φ_(Q)(t), respectively) of the one or more outbound symbolstreams 24 with in-phase and quadrature components (e.g., cos(ω_(RF)(t))and sin(ω_(RF)(t)), respectively) of one or more transmit localoscillations (TX LO) to produce mixed signals. One or more filtersfilter the mixed signals to produce one or more outbound up-convertedsignals (e.g., A(t)cos(ω_(BB)(t)+φ(t))+ω_(RF)(t))). In another example,the polar-Cartesian-based outbound symbol stream is up-sampled anddiscrete digitally filtered to produce the one or more up-convertedsignals. One or more power amplifiers amplify the outbound up-convertedsignal(s) to produce an outbound RF signal(s) 26.

For a super heterodyne topology, the transmitter section 14 includes abaseband (BB) to intermediate frequency (IF) section and an IF to aradio frequency (RF section). The BB to IF section may be of apolar-based topology, a Cartesian-based topology, a hybridpolar-Cartesian-based topology, or a mixing stage to up-convert theoutbound symbol stream(s) 24. In the three former cases, the BB to IFsection generates an IF signal(s) (e.g., A(t)cos(ω_(IF)(t)+φ(t))) andthe IF to RF section includes a mixing stage, a filtering stage and thepower amplifier driver (PAD) to produce the pre-PA outbound RFsignal(s).

When the BB to IF section includes a mixing stage, the IF to RF sectionmay have a polar-based topology, a Cartesian-based topology, or a hybridpolar-Cartesian-based topology. In this instance, the BB to IF sectionconverts the outbound symbol stream(s) 24 (e.g.,A(t)cos(ω_(BB)(t)+φ(t))) into intermediate frequency symbol stream(s)(e.g., A(t)(ω_(IF)(t)+φ(t)). The IF to RF section converts the IF symbolstream(s) into the outbound RF signal(s) 26.

The power amplifier, which includes one or more power amplifiers coupledin series and/or in parallel, outputs the amplified outbound RFsignal(s) 26 to the antenna interface 12. In an example, a RX-TXisolation module of the antenna interface 12 (which may be a duplexer, acirculator, or transformer balun, or other device that providesisolation between a TX signal and an RX signal using a common antenna)attenuates the outbound RF signal(s) 26. The RX-TX isolation module mayadjusts it attenuation of the outbound RF signal(s) 26 (i.e., the TXsignal) based on control signals 28 received from the basebandprocessing module 20. For example, when the transmission power isrelatively low, the RX-TX isolation module may be adjusted to reduce itsattenuation of the TX signal.

Continuing with the preceding example, an antenna tuning unit (ATU) ofthe antenna interface 12 is tuned to provide a desired impedance thatsubstantially matches that of the antenna assembly 10. As tuned, the ATUprovides the attenuated TX signal from the RX-TX isolation module to theantenna assembly 10 for transmission. Note that the ATU may becontinually or periodically adjusted to track impedance changes of theantenna assembly 10. For example, the baseband processing module 20 maydetect a change in the impedance of the antenna assembly 10 and, basedon the detected change, provide control signals 28 to the ATU such thatit changes it impedance accordingly.

The antenna assembly 10 also receives one or more inbound RF signals,which are provided to one of the ATUs of the antenna interface 12 viathe frequency band (FB) switch of the antenna interface 12. The ATUprovides the inbound RF signal(s) 30 to the RX-TX isolation module,which routes the signal(s) to the receiver (RX) section 18. The discretedigital RX section 18 converts (e.g., directly or in a super heterodynemanner) the inbound RF signal(s) 30 (e.g., A(t)cos(ω_(RF)(t)+φ(t))) intoone or more inbound symbol streams 32 (e.g., A(t)cos(ω_(BB)(t)+φ(t))).Various embodiments of the discrete digital receiver section 18 arediscussed in one or more of FIGS. 4-114.

The baseband processing module 20 converts the inbound symbol stream(s)32 into inbound data 34 (e.g., voice, text, audio, video, graphics,etc.) in accordance with one or more wireless communication standards(e.g., GSM, CDMA, WCDMA, HSUPA, HSDPA, WiMAX, EDGE, GPRS, IEEE 802.11,Bluetooth, ZigBee, universal mobile telecommunications system (UMTS),long term evolution (LTE), IEEE 802.16, evolution data optimized(EV-DO), etc.). Such a conversion may include one or more of: digitalintermediate frequency to baseband conversion, time to frequency domainconversion, space-time-block decoding, space-frequency-block decoding,demodulation, frequency spread decoding, frequency hopping decoding,beamforming decoding, constellation demapping, deinterleaving, decoding,depuncturing, and/or descrambling. Note that the processing module 20converts a single inbound symbol stream 32 into the inbound data 34 forSingle Input Single Output (SISO) communications and/or for MultipleInput Single Output (MISO) communications and converts the multipleinbound symbol streams 32 into the inbound data 34 for Single InputMultiple Output (SIMO) and Multiple Input Multiple Output (MIMO)communications.

The power management unit 20, if included, performs a variety offunctions. Such functions include monitoring power connections andbattery charges, charging a battery when necessary, controlling power tothe other components of the wireless transceiver and/or the portablecomputing communication device, generating supply voltages, shuttingdown unnecessary modules, controlling sleep modes of the modules, and/orproviding a real-time clock. To facilitate the generation of powersupply voltages, the power management unit may includes one or moreswitch-mode power supplies and/or one or more linear regulators.

FIG. 2 is a schematic block diagram of an embodiment of a multiple inputmultiple output (MIMO) wireless transceiver 36 that includes an antennaassembly 10, an antenna interface 12, a transmitter section 14, aclocking circuit module 16, a discrete digital receiver section 18, anda baseband processing module 20. The antenna assembly 10 may include oneor more antennas, one or more antenna arrays, a diversity antennastructure, one or more separate transmit antennas, one or more separatereceive antennas, and/or a combination thereof. The antenna interface 12includes one or more antenna tuning units, one or more transmissionlines, one or more impedance matching circuits, one or more transformerbaluns, one or more transmit-receive switches, one or moretransmit-receive isolation modules, etc. The wireless transceiver 36 mayfurther include a power management module (not shown).

The wireless transceiver 36 may be included within a portable computingcommunication device, which may be any device that can be carried by aperson, can be at least partially powered by a battery, and/or performsone or more software applications. For example, the portable computingcommunication device may be a cellular telephone, a laptop computer, apersonal digital assistant, a video game console, a video game player, apersonal entertainment unit, a tablet computer, etc. Note that thewireless radio transceiver 36 may operate in the radio frequency (RF)frequency spectrum and/or the millimeter wave (MMW)) frequency spectrum.

In an example of operation, the baseband processing module 20 performsone or more functions of the portable computing communication devicethat require wireless transmission of data. In this instance, thebaseband processing module 20 receives or generates outbound data 22(e.g., voice, text, audio, video, graphics, etc.) and converts it intomultiple outbound symbol streams 24 in accordance with one or morewireless communication standards that supports MIMO communications(e.g., GSM, CDMA, WCDMA, HSUPA, HSDPA, WiMAX, EDGE, GPRS, IEEE 802.11,Bluetooth, ZigBee, universal mobile telecommunications system (UMTS),long term evolution (LTE), IEEE 802.16, evolution data optimized(EV-DO), etc.). Such a conversion may include one or more of: digitalintermediate frequency to baseband conversion, time to frequency domainconversion, space-time-block decoding, space-frequency-block decoding,demodulation, frequency spread decoding, frequency hopping decoding,beamforming decoding, constellation demapping, deinterleaving, decoding,depuncturing, and/or descrambling.

The transmitter section 14, which includes one or more are transmittersas described with reference to FIG. 1 or as may be subsequentlydescribed with reference to FIGS. 115-129, receives the multiple outputsymbol streams 24 and converts them into multiple outbound RF signals26. The transmitter section 14 provides the outbound RF signals 26 tothe antenna interface 12, which in turn provides the outbound RF signals26 to the antenna assembly 10 for transmission. Note that the antennainterface 12 may include one or more antenna tuning units, one or moretransmission lines, one or more impedance matching circuits, one or moretransformer baluns, one or more transmit-receive switches, one or moretransmit-receive isolation modules, etc. for each of the outbound RFsignals.

The antenna assembly 10 also receives inbound RF signals 32 that itprovides to the discrete digital receiver section 18 via the antennainterface 12. The discrete digital receiver section 18 includes one ormore discrete digital receivers to convert the inbound RF signals 30into inbound symbol streams 32. The baseband processing module 20converts the inbound symbol streams 32 into inbound data 34 inaccordance with one or more wireless communication standards thatsupports MIMO communications (e.g., GSM, CDMA, WCDMA, HSUPA, HSDPA,WiMAX, EDGE, GPRS, IEEE 802.11, Bluetooth, ZigBee, universal mobiletelecommunications system (UMTS), long term evolution (LTE), IEEE802.16, evolution data optimized (EV-DO), etc.). Such a conversion mayinclude one or more of: digital intermediate frequency to basebandconversion, time to frequency domain conversion, space-time-blockdecoding, space-frequency-block decoding, demodulation, frequency spreaddecoding, frequency hopping decoding, beamforming decoding,constellation demapping, deinterleaving, decoding, depuncturing, and/ordescrambling.

The power management unit, if included, performs a variety of functions.Such functions include monitoring power connections and battery charges,charging a battery when necessary, controlling power to the othercomponents of the wireless transceiver 36 and/or the portable computingcommunication device, generating supply voltages, shutting downunnecessary modules, controlling sleep modes of the modules, and/orproviding a real-time clock. To facilitate the generation of powersupply voltages, the power management unit may includes one or moreswitch-mode power supplies and/or one or more linear regulators.

FIG. 3 is a schematic block diagram of an embodiment of a multiplefrequency band wireless transceiver 38 that includes a plurality ofantenna assemblies 10, a plurality of antenna interfaces 12, atransmitter section 14, a clocking circuit module 16, a discrete digitalreceiver section 18, and a baseband processing module 20. Each of theantenna assemblies 10 may include one or more antennas, one or moreantenna arrays, a diversity antenna structure, one or more separatetransmit antennas, one or more separate receive antennas, and/or acombination thereof. Each of the antenna interfaces 12 includes one ormore antenna tuning units, one or more transmission lines, one or moreimpedance matching circuits, one or more transformer baluns, one or moretransmit-receive switches, one or more transmit-receive isolationmodules, etc. The wireless transceiver 38 may further include a powermanagement module (not shown).

The wireless transceiver 38 may be included within a portable computingcommunication device, which may be any device that can be carried by aperson, can be at least partially powered by a battery, and/or performsone or more software applications. For example, the portable computingcommunication device may be a cellular telephone, a laptop computer, apersonal digital assistant, a video game console, a video game player, apersonal entertainment unit, a tablet computer, etc. Note that thewireless radio transceiver 38 may operate in the radio frequency (RF)frequency spectrum and/or the millimeter wave (MMW)) frequency spectrum.

In an example of operation, the baseband processing module 20 performsone or more functions of the portable computing communication devicethat require wireless transmission of data (e.g., a single concurrentcommunication) and/or transmission of multiple data (e.g., multipleconcurrent communications). In this instance, the baseband processingmodule 20 receives or generates multiple outbound data (e.g., one foreach communication) and converts the into multiple outbound symbolstreams (e.g., one for each communication where the standards may beGSM, CDMA, WCDMA, HSUPA, HSDPA, WiMAX, EDGE, GPRS, IEEE 802.11,Bluetooth, ZigBee, universal mobile telecommunications system (UMTS),long term evolution (LTE), IEEE 802.16, evolution data optimized(EV-DO), etc.). Each conversion of outbound data into outbound symbolstreams may include one or more of: digital intermediate frequency tobaseband conversion, time to frequency domain conversion,space-time-block decoding, space-frequency-block decoding, demodulation,frequency spread decoding, frequency hopping decoding, beamformingdecoding, constellation demapping, deinterleaving, decoding,depuncturing, and/or descrambling.

The transmitter section 14, which includes a plurality of transmittersas described with reference to FIG. 1 or as may be subsequentlydescribed with reference to FIGS. 115-129, receives the multiple outputsymbol streams and converts each of them into an outbound RF signal inaccordance with the corresponding standard. The transmitter section 14provides each of the outbound RF signals to a corresponding one of theantenna interfaces, which in turn provides the outbound RF signals to acorresponding one of the antenna assemblies 10 for transmission.

Each of the antenna assemblies 10 also receives inbound RF signals thatit provides to the discrete digital receiver section 18 via acorresponding one of the antenna interfaces 12. The discrete digitalreceiver section 18 includes one or more discrete digital receivers toconvert each of the inbound RF signals into multiple inbound symbolstreams. The baseband processing module 20 converts each of the inboundsymbol streams into separate inbound data in accordance with one or morewireless communication standards (e.g., GSM, CDMA, WCDMA, HSUPA, HSDPA,WiMAX, EDGE, GPRS, IEEE 802.11, Bluetooth, ZigBee, universal mobiletelecommunications system (UMTS), long term evolution (LTE), IEEE802.16, evolution data optimized (EV-DO), etc.). Such a conversion mayinclude one or more of: digital intermediate frequency to basebandconversion, time to frequency domain conversion, space-time-blockdecoding, space-frequency-block decoding, demodulation, frequency spreaddecoding, frequency hopping decoding, beamforming decoding,constellation demapping, deinterleaving, decoding, depuncturing, and/ordescrambling.

The power management unit, if included, performs a variety of functions.Such functions include monitoring power connections and battery charges,charging a battery when necessary, controlling power to the othercomponents of the wireless transceiver and/or the portable computingcommunication device, generating supply voltages, shutting downunnecessary modules, controlling sleep modes of the modules, and/orproviding a real-time clock. To facilitate the generation of powersupply voltages, the power management unit may includes one or moreswitch-mode power supplies and/or one or more linear regulators.

FIG. 4 is a schematic block diagram of an embodiment of a receiver ofone or more of the transceivers of FIGS. 1-3 that includes a band passfilter (BPF) 40, a sample and hold filter circuit 44, a discrete timefilter 46, and a conversion module 49, which may include a downconversion module 48 and/or an analog to digital converter (ADC) 50. Thereceiver 18 may further include a low noise amplifier (LNA) module 42(e.g. one or more low noise amplifiers coupled in series and/or inparallel) and a clock circuit module 16. The clock circuit module 16includes a clock generator 52, a sample and hold (S&H) clock circuit 54,a filter clock circuit 54, a local oscillation (LO) clock circuit 56,and an analog to digital converter (ADC) clock circuit 58.

In an example of operation, the band pass filter 40 receives an inboundwireless (e.g., RF or MMW) signal from the antenna interface. The bandpass filter 40 attenuates out of band signal components and passes,substantially unattenuated, in-band signal components of the inbound RFsignal (e.g., a filtered inbound wireless signal). The low noiseamplifier 42 amplifies the filtered inbound RF signal to produce anamplified inbound RF signal. With reference to FIG. 5, an inbound RFsignal is shown in the frequency domain to have in-band signalcomponents centered about an RF or MMW (millimeter wave) carrierfrequency and out of band signal components at the edges of the signal.The output of the low noise amplifier 42 is shown in the frequencydomain to substantially attenuate the out of band signal components andto pass, substantially unattenuated, the inbound signal components ofthe inbound RF signal.

Returning to the discussion of FIG. 4, the sample and hold filter 44receives the amplified inbound RF signal and samples it in accordancewith a sample clock signal and a hold clock signal, wherein the sampleand hold clock signals have at a rate corresponding to a multiple of thebandwidth of the filtered inbound wireless signal (e.g., =>2*bandwidthof the inbound wireless signal). With reference to FIG. 6, the sampleand hold circuit 44 receives the amplified inbound RF signal (shown inthe frequency domain) and samples it at a sampling frequency (fs). Inthis example, the sampling frequency is greater than or equal to twotimes the bandwidth of the amplified inbound RF signal. In general, thebandwidth of the amplified inbound RF signal corresponds to thebandwidth of the baseband signal component of the inbound RF signal. Forinstance, the bandwidth of the baseband inbound signal may be a fewhundred kilohertz to tens of megahertz. The sample and hold filter 44outputs, in the frequency domain, a plurality of pulses spaced infrequency by the sampling frequency (i.e., a frequency domain pulsetrain). The sample and hold output includes a pulse at RF, whichcorresponds to the original inbound RF signal. The functionality of thesample and hold circuit 44 will describe in greater detail withreference to FIGS. 7 through 32.

Returning to the discussion of FIG. 4, the discrete time filter 46(which may be a finite impulse response filter, an infinite impulseresponse filter, a frequency translation bandpass filter, and/or othertype of discrete filter) receives the output of the sample and holdfilter circuit and filters it. Depending on the filtering response ofthe discrete time filter, the discrete time filter will output, in thefrequency domain, a single pulse of the sample and hold output at aparticular frequency (i.e., a filtered sample pulse). For example, ifthe filtering response of the discrete time filter corresponds to abandpass filter 40 centered at RF, the discrete time filter 46 willoutput the pulse at RF and attenuate the pulses at the otherfrequencies. As another example, if the filter response of discrete timefilter corresponds to a bandpass filter 40 centered at an intermediatefrequency, the discrete time filter 46 will output the pulse at theintermediate frequency and attenuate the pulses at the otherfrequencies. Various embodiments of a discrete time filter 46 will bedescribed in greater detail with reference to FIGS. 33-37.

The conversion module 49 is operable to convert the filtered samplepulse into an inbound baseband signal. In one example, the discrete timefilter module 46 outputs the filtered sample pulse at baseband. In thisexample, the conversion module includes the analog to digital converter50, which converts the filtered sample pulse into the inbound basebandsignal.

In another example, the conversion module 49 includes the downconversion module 48 and the ADC 50. In this example, the downconversion module 48 may be implemented using analog circuitry (e.g., amixer, a local oscillation, and one or more pass filters) or it may beimplemented as discrete time digital circuitry (e.g., a sample and holdcircuit 44 and a discrete time filter 46). Regardless of theimplementation, the down conversion module 48 converts the output of thediscrete time filter 46 to a baseband signal (e.g., an analog symbolstream). The analog to digital converter 50 converts the baseband signalinto a digital signal (e.g., an inbound symbol stream), which may beprocess as previously described with reference to FIGS. 1-3.

The clock circuit module 16 (or clock generation circuit) includes aclock generation module 50, a sample and hold (S&H) clock module 52, adiscrete time filter clock module 54, and a conversion module clock(e.g., the ADC clock module 58, which may further include the downconversion (LO) clock module 56). The clock generation module 60 (e.g.,a phase locked loop, a crystal oscillator, a digit frequencysynthesizer, etc.) is operable to generate a system clock signal at adesired frequency (e.g., 1 GHz to hundreds of GHz).

The S&H clock module 52 (e.g., a phase locked loop, a clock ratedivider, a clock rate multiplier, etc.) generates a sample and holdclock signal from the system clock signal to have a rate thatcorresponds to the multiple of the bandwidth of the filtered inboundwireless signal (e.g., 2*BW of inbound signal). The S&H clock signal mayinclude a sample clock signal having a duty cycle and a hold clocksignal having a duty cycle. The duty cycles of the sample clock signaland the hold clock signal may be the same or different and may affectthe frequency response of the sample and hold module as is furtherdiscussed with reference to one or more of FIGS. 7-18.

The discrete time filter clock module 54 (e.g., a phase locked loop, aclock rate divider, a clock rate multiplier, etc.) generates a filterclock from the system clock signal. The conversion clock module (e.g.,one or more of a phase locked loop, a clock rate divider, a clock ratemultiplier, etc.) generates a conversion clock signal (e.g., an ADCclock signal and may further include a down conversion clock signal)from the system clock signal.

FIGS. 7-18 illustrate one or more examples of the operation of thesample and hold filter circuit within a receiver of FIG. 4 and/or of anyof the other figures. FIGS. 19-29 illustrates one or more embodiments ofthe sample and hold circuit that may be used within a receiver asdiscussed herein.

FIG. 7 is a diagram of an example of an input signal g(t) in the timedomain. The signal may be representative of a baseband communicationsignal having one or more channels and or subcarriers. For example, inan OFDM (orthogonal frequency division multiplexing) scheme, thebaseband is divided into a plurality of subcarriers, where some of thesubcarriers carry encoded data. As another example, the input signalg(t) may represent a sinusoidal signal, a complex sinusoidal signal, orother type of signal. Generally, the input signal g(t) may be expressedas a sum of sinusoidal signals (e.g., g(t)=A₁ cos(ω₁(t)+A₂ cos(ω₂(t)+A₃cos(ω₃(t)+ . . .

FIG. 8 is a diagram of an example of the sample and hold input signalG(f) in the frequency domain. In this example, the frequency domainrepresentation of the signal is centered at 0 Hz with a bandwidth thatspans from −fc to +fc, where fc corresponds to the highest frequencycomponent of the time domain input signal g(t). As another example, ifthe input signal corresponds to a baseband communications signal havinga bandwidth of 2 MHz, then fc is 2 MHz.

FIG. 9 is a diagram of an example of sample and hold input signal g(t)being sampled at a given sampling period (T_(s)) to produce a pluralityof sample pulses g_(s)(t). Each sample pulse has a magnitudecorresponding to the magnitude of the input signal g(t) at thecorresponding sampling point. Note that the sampling period (Ts)corresponds to the inverse of the sampling frequency (fs) and thesampling frequency (fs) is equal to or greater than twice the highestfrequency components of the input signal g(t) (i.e., fs>=2*fc).

FIG. 10 is a diagram of an example of the sampled inbound signal (e.g.,g_(s)(t) in the frequency domain, which is expressed as G_(s)(f). Inthis example, the frequency domain representation of the sampled signalG_(s)(f) includes the frequency domain representation of the originalsignal (e.g., the one shown in FIG. 8) and images of the original signalat frequencies corresponding to the sampling frequency and multiples ofthe sampling frequency. Note that while the sampling frequency should beat least twice the highest frequency components of the input signal(e.g., fs>=2*fc), the present example has the sampling frequency atapproximately 4 times the highest frequency component of the inputsignal (e.g., fs≅4*fc).

FIG. 11 is a diagram of an example of sampling and holding the inputsignal g(t) in the time domain. As shown in FIG. 9, the sampling of theinput signal produces a plurality of sample pulses at an intervalcorresponding to the sampling period (Ts). For each sampled pulse, it isheld for a holding period (Th), which is less than or equal to thesampling period (Ts), to produce a plurality of sampled and held pulses(e.g., g_(sh)(t). In the present example, the holding period isapproximately ½ of the sampling period.

FIG. 12 is a diagram of an example of the sampled and held signal (e.g.,g_(sh)(t) in the frequency domain, which is expressed as G_(sh)(f). Theexample further illustrates various sample and hold filtering responsesfor different ratios of T_(s)-to-T_(h). In this example, G_(sh)(f)includes a plurality of sampled and held pulses at frequency intervalscorresponding to the sampling frequency and multiples thereof. Inaddition, the example includes various filter responses for the sampleand hold filter circuit based on ratios of the sampling period (Ts) tothe holding period (Th). For instance, as the ratio of the holdingperiod to the sampling period approaches one, the filter response of thesample and hold filter circuit more closely approximates a sin X/Xwaveform. Accordingly, by varying the ratio of the holding period to thesampling period, the filter response of the sample and hold filtercircuit may be varied.

FIG. 13 is a diagram of an example of an input RF signal g(t) in thetime domain. The signal may be representative of an RF modulatedcommunication signal having one or more channels and or subcarriers. Forexample, in an OFDM (orthogonal frequency division multiplexing) scheme,the baseband is divided into a plurality of subcarriers, which are upconverted to RF signals. As another example, the input signal g(t) mayrepresent a communication signal that is transmitted in the RF and/orMMW frequency bands in accordance with one or more wirelesscommunication standards. Generally, the inbound RF signal g(t) may beexpressed g(t)=A(t)*cos(ω_(RF)(t)+ω_(SIG)(t)+φ(t)), A(t) representsamplitude information of the baseband signal, ω_(RF)(t) represents theRF carrier frequency, ω_(SIG)(t) represents the frequency of thebaseband signal, and φ(t) represents phase information of the basebandsignal.

FIG. 14 is a diagram of an example of the inbound RF signal (e.g., g(t))in the frequency domain, which is expressed as G(f). as shown, thefrequency domain representation of the inbound RF signal includes afrequency domain pulse at the RF frequency and the correspondingnegative RF frequency. The bandwidth of the frequency domain pulsecorresponds to the largest signal component of the baseband signal(e.g., SIG(t)=A(t)cos(ω_(SIG)(t)+φ(t)).

FIG. 15 is a diagram of an example of the inbound RF signal, in thefrequency domain, being sampled at a sampling frequency (f_(s)), whichmay be expressed as G_(sh)(f). In this example, a frequency domain pulseis positioned in frequency based on the sampling frequency and multiplesthereof. The plurality of frequency domain pulses includes the originalfrequency domain pulses of FIG. 14. In this example, the samplingfrequency is approximately equal to ¼ the RF frequency and frequencypulse train is shown without sample and hold filtering.

FIG. 16 is a diagram of an example of the frequency domainrepresentation of the sampled and held inbound RF signal G_(sh)(f) beingfiltered by the sample and hold filtering circuit. In this example, theholding period (Th) is much less than ¼ of the sampling period (Ts),which yields a relatively flat sin X/X filtering response between −RFand RF. In general, the frequency pulse at 0 Hz will have lessdistortion than frequency pulses at other frequencies, however, withthis type of sample and hold filtering, the distortion in the rangeillustrated may be negligible.

FIG. 17 is a diagram of another example of the frequency domainrepresentation of the sampled and held inbound RF signal G_(sh)(f) beingfiltered by the sample and hold filtering circuit. In this example, theholding period (Th) is approximately ¼ of the sampling period (Ts),which yields a bandpass filter response between −RF and RF.

FIG. 18 is a diagram of another example of the frequency domainrepresentation of the sampled and held inbound RF signal G_(sh)(f) beingfiltered by the sample and hold filtering circuit. In this example, theholding period (Th) is approximately equal to the sampling period (Ts),which yields a sin X/X response between −RF and RF.

FIGS. 19-32 illustrate one or more embodiments and/or one or morecomponents a sample and hold module that may be used in a receiver or ina transmitter and will be discussed in greater detail below. In general,a sample and hold module includes a sample switching module, animpedance module (e.g., a capacitor, a capacitor-inductor circuit, andan active element capacitor-inductor circuit), and a hold switchingmodule. The sample switching module (e.g., one or more transistors,switches, etc.) outputs samples of an inbound wireless signal inaccordance with a sampling clock signal. The impedance moduletemporarily stores the samples of the inbound wireless signal. The holdswitching module (e.g., one or more transistors, switches, etc.) outputsa filtered representation of the samples in accordance with a hold clocksignal to produce a frequency domain sample pulse train.

The sample and hold clock module generates the sampling clock signal andthe hold clock signal in accordance with a sample and hold clock controlsignal, which is generated by a processing module. In an example, theprocessing module generates the sample and hold clock control signal tofacilitate establishing the filter response of the sample and holdmodule, wherein the filter response of the sample and hold module is inaccordance with a ratio between the sampling clock signal and the holdclock signal.

FIG. 19 is a schematic block diagram of an embodiment of a sample andhold filter circuit 44 that includes a sample driver 62, a sample switch64, a sample impedance 66, a hold driver 68, a hold switch 70, and ahold impedance 72. Each of the impedances (Z) 66 and 72 may be one ormore capacitors (which may be implemented as shown in FIG. 21), aresistor-capacitor circuit, an active impedance, or a tank circuit(which may be implemented as shown in FIG. 22).

In an example of operation, an input signal is provided to the input ofthe sample driver. When activated by the sample clock 74 (which isactive for a sampling period at the sampling frequency), the sampledriver 62 drives the input signal on to the impedance 66, which imposesthe magnitude of the input signal on the impedance 66. While the sampleswitch 64 is closed, the voltage imposed on the impedance substantiallymatches the voltage of the input signal. When the sample switch 64opens, the sample impedance 66 has the most recent voltage of the inputsignal imposed thereon.

After the sample switch 64 opens and before it closes again for the nextsample, the hold switch 70 is closed (which is toggled for a holdingperiod at the sampling frequency) in accordance with the hold clock 76.With the hold switch 70 closed, the hold driver 68 imposes the voltageimposed on the sample impedance 66 on to the hold impedance 72. Thevoltage on the hold impedance 66 may be read at any time after the holdswitch 64 is closed and the voltage on the hold impedance 72 issubstantially stable. The process repeats for the next sample and holdinterval. Note that there are a variety of ways to implement the drivers62 and 68, the switches 64 and 70, and/or the impedances 66 and 72.

FIG. 20 is a schematic block diagram of another embodiment of a sampleand hold filter circuit 44 that includes a sample driver 62, a sampleswitch 64, a sample impedance 66, a hold driver 68, and a hold switch70. Each of the impedances (Z) 66 may be one or more capacitors 78(which may be implemented as shown in FIG. 21), a resistor-capacitorcircuit 80, an active impedance, or a tank circuit (which may beimplemented as shown in FIG. 22).

In an example of operation, an input signal is provided to the input ofthe sample driver. When activated by the sample clock 74 (which istoggled for a sampling period at the sampling frequency), the sampledriver 62 drives the input signal on to the impedance 66, which imposesthe magnitude of the input signal on the impedance 66. While the sampleswitch 64 is closed, the voltage imposed on the impedance substantiallymatches the voltage of the input signal. When the sample switch 64opens, the sample impedance 66 has the most recent voltage of the inputsignal imposed thereon.

After the sample switch 64 opens and before it closes again for the nextsample, the hold switch 70 is closed (which is toggled for a holdingperiod at the sampling frequency). With the hold switch 70 closed, thehold driver 68 outputs the voltage imposed on the sample impedance 66.The process repeats for the next sample and hold interval.

FIG. 23 is a schematic block diagram of another embodiment of a sampleand hold filter circuit 44 that includes a sample driver 62, a sampleswitch 64, a sample impedance circuit (Z ckt) 82, a hold driver 68, ahold switch 70, a control module 84 (e.g., a module of the basebandprocessing module), and a hold impedance circuit 86. Each of theimpedance circuits (Z ckt) 82 and 86 includes a circuit that has afrequency response in a frequency range of interest of the sample andhold process. For example, the impedance circuit 82 and 86 may be acapacitor-inductor-capacitor filter 88 (as shown in FIG. 25) that istuned to the frequency of the input signal (e.g., RF), is tuned to thesampling frequency (fs), is tuned to a multiple of the samplingfrequency, or is tuned to baseband. As a more specific example, thecapacitor C2 and the inductor L may be tuned to RF, such that RF signalspass substantially unattenuated to capacitor C1, which stores thevoltage of the input signal during the sampling period.

Another example of the impedance circuit 82 and 86 includes one or moreactive components (e.g., an operational amplifier, transistor, etc.)that is configured to produce a desired frequency response at RF, at fs,at n*fs, or at baseband. The impedance circuit 82 and 86 furtherincludes a storage element (e.g., a capacitor). The desired frequencyresponse may be a notch filter response, a bandpass filter response, ahigh pass filter response, a low pass filter response, etc. For example,the impedance circuit 90 of FIG. 26 may be implemented to provide a bandpass filter at RF such that RF signals pass substantially unattenuatedto capacitor C1, which stores the voltage of the input signal during thesampling period.

In an example of operation, an input signal is provided to the input ofthe sample driver 62. When activated by the sample clock 74 (which istoggled for a sampling period at the sampling frequency), the sampledriver 62 drives the input signal to the impedance circuit 82. Theimpedance circuit 82 filters the input signal in accordance with itsfrequency response and stores a filtered representation of the inputsignal on a storage element (e.g., a capacitor). While the sample switch64 is closed, the voltage stored by the sample impedance circuit 82substantially matches the voltage of the input signal provided that theinput signal is within the unattenuated region of the filter response ofthe sample impedance circuit 82. When the sample switch 64 opens, thesample impedance circuit 82 is storing the most recent voltage of theinput signal.

After the sample switch 64 opens and before it closes again for the nextsample, the hold switch 70 is closed (which is toggled for a holdingperiod at the sampling frequency). With the hold switch 70 closed, thehold driver 68 provides the voltage stored in the sample impedancecircuit 82 to the hold impedance circuit 86, which stores a filteredrepresentation of the inputted sample on a storage element (e.g., acapacitor). While the hold switch 70 is closed, the voltage being storedby the hold impedance circuit 86 substantially matches the voltagestored by the sample impedance circuit 86 provided that the input signalis within the unattenuated region of the filter response of the holdimpedance circuit 86. The voltage stored by the hold impedance circuit86 may be read at any time after the hold switch 70 is closed and thevoltage stored by the hold impedance circuit 86 is substantially stable.The process repeats for the next sample and hold interval.

FIG. 24 is a schematic block diagram of another embodiment of a sampleand hold filter circuit 44 that includes a sample driver 62, a sampleswitch 64, a sample impedance circuit (Z ckt) 82, a hold driver 68, anda hold switch 70. Each of the impedance circuits (Z ckt) 82 includes acircuit that has a frequency response in a frequency range of interestof the sample and hold process. For example, the impedance circuit 82may be a capacitor-inductor-capacitor filter 88 (as shown in FIG. 25)that is tuned to the frequency of the input signal (e.g., RF), is tunedto the sampling frequency (fs), is tuned to a multiple of the samplingfrequency, or is tuned to baseband. Another example of the impedancecircuit 82 may be implemented as shown in FIG. 26.

In an example of operation, an input signal is provided to the input ofthe sample driver 62. When activated by the sample clock 74, the sampledriver 62 drives the input signal to the impedance circuit 82. Theimpedance circuit 82 filters the input signal in accordance with itsfrequency response and stores a filtered representation of the inputsignal on a storage element (e.g., a capacitor). While the sample switch64 is closed, the voltage stored by the sample impedance circuit 82substantially matches the voltage of the input signal provided that theinput signal is within the unattenuated region of the filter response ofthe sample impedance circuit 82. When the sample switch 64 opens, thesample impedance circuit 82 stores the most recent voltage of the inputsignal.

After the sample switch 64 opens and before it closes again for the nextsample, the hold switch 70 is closed. With the hold switch 70 closed,the hold driver 68 outputs the voltage stored in the sample impedancecircuit 82. At the next sample period, the process repeats.

FIG. 27 is a diagram of an example of the frequency domainrepresentation of the sampled and held inbound RF signal G_(sh)(f) (ofFIG. 15) being filtered by the sample and hold filtering circuit of FIG.23 or 24. In this example, the holding period (Th) is much less than ¼of the sampling period (Ts), which yields a relatively flat sin X/Xfiltering response between −RF and RF. The impedance circuits of thesample and hold circuit filter are tuned, via the processing module, toprovide a bandpass filter centered at RF. As such, the filteringprovided by the impedance circuits pass, substantially unattenuated, theoriginal RF frequency pulses and attenuate the other frequency pulses.

FIG. 28 is a diagram of another example of the frequency domainrepresentation of the sampled and held inbound RF signal G_(sh)(f) (ofFIG. 15) being filtered by the sample and hold filtering circuit of FIG.23 or 24. In this example, the holding period (Th) is much less than ¼of the sampling period (Ts), which yields a relatively flat sin X/Xfiltering response between −RF and RF. The impedance circuits of thesample and hold circuit filter are tuned, via the processing module, toprovide a bandpass filter centered at fs (i.e., the sample frequency).As such, the filtering provided by the impedance circuits pass,substantially unattenuated, the frequency pulses at the sample frequency(−fs and fs) and attenuate the other frequency pulses.

FIG. 29 is a diagram of another example of the frequency domainrepresentation of the sampled and held inbound RF signal G_(sh)(f) (ofFIG. 15) being filtered by the sample and hold filtering circuit of FIG.23 or 24. In this example, the holding period (Th) is much less than ¼of the sampling period (Ts), which yields a relatively flat sin X/Xfiltering response between −RF and RF. The impedance circuits of thesample and hold circuit filter are tuned, via the processing module, toprovide a bandpass filter baseband. As such, the filtering provided bythe impedance circuits pass, substantially unattenuated, the frequencypulses at the baseband and attenuate the other frequency pulses.

FIG. 30 is a schematic block diagram of an embodiment of a sample andhold clock generator circuit 92 coupled to the clock generator 94. TheS&H clock circuit 96 includes a clock rate adjust module 98, a phaseshift module 100, a control module 102, a plurality of switch modules104, and a plurality of logic circuits 106.

In an example of operation, the clock rate adjust module 98 receives asource clock 108 from the clock generator 94 and adjusts the rate of thesource clock 108 up, down, or null to produce a clock signal at thedesired sampling frequency 110. The clock rate adjust module 98 may beimplemented as a programmable clock divider, programmable clockmultiplier, a digital frequency synthesizer, a phase locked loop, and/ora combination thereof.

The phase shift module 100, which may be implemented by an adjustabledelay line, produces a plurality of phase shift representations of theclock signals at the desired sampling frequency. With reference to FIG.31, the phase shift module 100 may output a plurality of phased shiftedclock signals wherein the first phase shifted clock signal correspondsto the original clock signal and the remaining phase shifted clocksignals are successively offset from the first phase shifted clocksignal by a phase offset 120 (e.g., a few degrees to 10's of degrees).

Returning to the discussion of FIG. 30, each of the switch modules 104receives the plurality of phase shifted clock signals. Based on one ormore control signals from the control module 102, a switching module 104selects one of the phase shifted clock signals to represent the risingedge of the clock signal 112 (e.g., the sample (S) clock 116 or the hold(H) clock 118) and selects another one of the phase shifted clocksignals to represent the falling edge of the clock 114 (e.g., the sample(S) clock 116 or the hold (H) clock 118). The logic circuit 106 utilizesthe selected signals to generate the corresponding clock signal (e.g.,the sample (S) clock 116 or the hold (H) clock 118).

For example and with reference to FIG. 32, the clock signal at thesampling frequency 110 may be selected to provide the rising edge 112 ofthe sample clock (S clk) 116 and a subsequent phase shifted clock signalis selected to provide the falling edge 114 of the sample clock 116. Thelogic circuit 106 combines the clock signals (e.g., a flip flop is setby the rising edge 112 of the first selected clock and reset by thefalling edge 114 of the other clock or some other combination of logiccircuits 106 to generate a rising edge 112 and falling edge 112 of thedesired clock signal from one or more of the selected clock signals) tothe desired clock signal. For example, the logic circuit 106 maygenerate the sample clock signal 116 to have a duty cycle that isgreater than, equal to, or less than the duty cycle of the clock signalat the sample frequency (e.g., clk @ fs). Note that the duty cycle ofthe clock signal at the sampling frequency may be adjustable 122 via theclock rate adjust module 98.

After a delay from the falling edge 114 of the sample clock (which maycorrespond to one or more phase offsets), a phase shifted clock isselected to provide the rising edge 112 of the hold clock (H clk) 118and a subsequent phase shifted clock is selected to provide the fallingedge 114 of the hold clock 118. The duty cycle of the hold clock 118 isselected to be a desired ratio to the duty cycle of the sample clock toprovide the desired bandpass sample and hold filtering. Note that moreor less phase shifted clock signals may be selected to generate thedesired sample clock or the desired hold clock 118.

In another example of a receiver, the receiver may include a sample andhold module, a programmable discrete time filter module and a conversionmodule, which converts filtered sample pulse into an inbound basebandsignal. The sample and hold module is operable to sample and hold, at arate corresponding to a multiple of a frequency-dependent component ofan inbound wireless signal, the inbound wireless signal to produce afrequency domain sample pulse train. Note that the frequency-dependentcomponent may be the bandwidth (BW) of the inbound wireless signal, anRF or MMW carrier frequency of the inbound wireless signal, the BW plusnearby interference signals of the inbound wireless signal, and/or theRF or MMW carrier frequency plus nearby interference signals of theinbound wireless signal.

The programmable discrete time filter module (which may be aprogrammable FIR filter, a programmable IIR filter, and/or aprogrammable FTBPF) is operable to generate control information (e.g.,controls and/or settings) in accordance with a desired bandpass filterresponse. The programmable discrete time filter module is then operableto establish one or more of bandpass region, gain, center frequency,roll-off, and quality factor in accordance with the control informationto produce a bandpass filter response. The programmable discrete timefilter module is then operable to filter, in accordance with thebandpass filter response, the frequency domain sample pulse train toproduce a filtered sample pulse.

FIG. 33 is a schematic block diagram of an embodiment of a programmablediscrete time filter 124 that includes a finite impulse response (FIR)topology coupled to the filter clock circuit 126. The programmable FIRfilter 124 includes a control module 128, a programmable delay line(e.g., a plurality of delay elements (e.g., Z⁻¹)), a plurality ofstages, a plurality of summing modules 130 (e.g., analog or digitaladders), and an output module 132 (e.g., a multiplexer, a switch module,etc.). Each stage includes a coefficient module 134 (e.g., a buffer), amultiplier 136, and a driver 138.

In an example of operation, the control module 128 sets the number ofstages to establish the desired response of the filter 124, sets thecoefficients 134 accordingly, and sets the controls 140 for the delayline (e.g., rise time, fall time, resetting or setting of flip-flops,etc.). The control module 128 receives information from the basebandprocessing module, which it uses to determine the particular settings142 and control signals 140 (i.e., it determines the desired filterresponse and the corresponding settings 142). The informationcorresponds to operation of the wireless transceiver, the operation ofthe receiver only, and/or some other factors that effect performance ofthe wireless transceiver or receiver. Alternatively, the basebandprocessing module determines the desired filter response and providesthe settings 142 and control signals 140 to the control module 128.

With the number of stages, coefficients 134, and control signals 140established, the first delay element of the delay line receives a firstsample and hold signal g_(sh)(t) from the sample and hold filtercircuit. The first stage also receives the inbound RF signal andprocesses it accordingly (e.g., scales the magnitude of the sample basedon the coefficient, etc.). At the next clock interval (or multiple clockintervals) as provided by the filter clock circuit 126, each of thefirst delay element and the first stage receives a second sample andhold signal and processes it accordingly. In addition, the previoussample and hold signal is provided to the second delay line element andto the second stage.

The programmable FIR filter 124 continues to receive sample and holdsignals from the sample and hold filter circuit and propagates themthrough the corresponding circuitry to produce an output 144. The output144 is a filtered representation of the output 144 of the sample andhold circuits, which corresponds to a filtered representation of theinbound RF signal at RF, at IF, at fs, or at baseband.

While the programmable FIR filter 124 is shown with a particularconfiguration, other configurations of the programmable FIR filter arepossible. For example, a stage of the programmable FIR filter mayinclude an amplifier stage instead of the coefficient module 134,multiplier 136, and driver 138. As another example, the delay elementsmay be independent delay devices (i.e., not part of the delay line) andmay be individually programmable (e.g., rise time, fall time, delay,etc.). As yet another example, the discrete time filter 124 may includea clock circuit to adjust the clock received from the filter clockcircuit 126.

FIG. 34 is a schematic block diagram of another embodiment of aprogrammable discrete time filter 124 having an infinite impulseresponse (IIR) topology coupled to the filter clock circuit 126. Theprogrammable IIR filter 124 includes a control module 128, twoprogrammable delay lines (e.g., one input set of delay elements (e.g.,Z⁻¹) and one output set of delay elements), a plurality of stages (e.g.,input and output stages, each stage including a coefficient register 134and a multiplier 136), a summing module 130 (e.g., analog or digitaladders), and a selection module 146 (e.g., a multiplexer, a switchmodule, etc.). Each stage includes a coefficient module 134 (e.g., abuffer), a multiplier 136, and may further include a driver (not shown).

In an example of operation, the control module 128 sets the number ofstages to establish the desired response of the filter 124 (e.g.,provides a select control signal 154 to the selection module 146),provides settings 150 to the coefficient registers 134 accordingly, andsets the controls for the delay lines 148 (e.g., rise time, fall time,resetting or setting of flip-flops, etc.). The control module 128receives information from the baseband processing module, which it usesto determine the particular settings and control signals (i.e., itdetermines the desired filter response and the corresponding settings).The information corresponds to operation of the wireless transceiver,the operation of the receiver only, and/or some other factors thateffect performance of the wireless transceiver or receiver.Alternatively, the baseband processing module determines the desiredfilter response and provides the settings and control signals to thecontrol module 128.

With the number of stages, coefficients 134, and control signals areestablished, the first delay element of the input delay line receives afirst sample and hold signal g_(sh)(t) from the sample and hold filtercircuit. The first input stage also receives the inbound RF signal andprocesses it accordingly (e.g., scales the magnitude of the sample basedon the coefficient, etc.). At the next clock interval (or multiple clockintervals) of the clock signal 152 as provided by the filter clockcircuit 126, each of the first input delay element and the first inputstage receives a second sample and hold signal and processes itaccordingly. In addition, the previous sample and hold signal isprovided to the second input delay line element, to the second inputstage, and to the summing module 130 via the selection module 146 toproduce a current output 144. The current output 144 is received by thefirst delay element of the output delay line.

The programmable IIR filter 124 continues to receive sample and holdsignals from the sample and hold filter circuit and propagates themthrough the corresponding circuitry to produce an output 144. The output144 is a filtered representation of the output 144 of the sample andhold circuits, which corresponds to a filtered representation of theinbound RF signal at RF, at IF, at fs, or at baseband.

While the programmable IIR filter 124 is shown with a particularconfiguration, other configurations of the programmable IIR filter 124are possible. For example, a stage of the programmable IIR filter 124may include an amplifier stage instead of the coefficient module 134,multiplier 136, and driver. As another example, the delay elements maybe independent delay devices (i.e., not part of the delay line) and maybe individually programmable (e.g., rise time, fall time, delay, etc.).As yet another example, the discrete time filter 124 may include a clockcircuit to adjust the clock received from the filter clock circuit 126.

FIG. 35 is a schematic block diagram of an embodiment of a frequencytranslation band pass filter (FTBPF) 156 coupled to filter the output ofthe sample and hold filter circuit 158. The FTBPF 156 includes aplurality of transistors 160 (e.g., a switching network) and a pluralityof baseband impedances 162 (Z_(BB)(s)).

In an example of operation, the FTBPF 156 provides a high-Q (qualityfactor) RF filter that filters the output of the sample and hold circuit158 such that desired frequency pulse (e.g., RF, IF, fs, or baseband) ispassed substantially unattenuated to the down conversion module 164 andundesired frequency pulses are attenuated. To achieve such a filter, thebaseband impedances 162 ((Z_(BB)(s)) collectively provide a low-Qbaseband filter having a corresponding filter response, where each ofthe baseband impedances 162 may be a capacitor, a switched capacitorfilter, a switch capacitor resistance, and/or a complex impedance. Notethat the impedance of each of the baseband impedances 162 may be thesame, different, or combination thereof. Further note that theimpedances of each of baseband impedances 162 may be adjusted viacontrol signal from the baseband processing module to adjust theproperties of the low-Q baseband filter 166 (e.g., bandwidth,attenuation rate, quality factor, etc.).

The low-Q baseband filter 166 is frequency translated to the desired RFfrequency to produce the high-Q RF filter 168 via the clock signals 172provided by the filter clock 170. FIG. 37 illustrates the frequencytranslation of the low-Q baseband filter 166 response to the high-Q RFfilter 168 response and FIG. 36 illustrates an embodiment of the filterclock circuit 170. As shown in FIG. 36, the filter clock circuit 170produces four clocks signals each having a 25% duty cycle andsequentially phase offset by 90°. The clock signals have a frequencycorresponding to the carrier frequency of the desired frequency pulseand can be adjusted to better track the desired frequency pulse.

Returning to the discussion of FIG. 35, the FTBPF 156 receives the clocksignals 172, which are coupled to the transistors 160 to sequentiallycouple their respective baseband impedances 162 to the output of thesample and hold filter circuit 158. With the clock rate being at thedesired frequency pulse (e.g., at the RF pulse), the low-Q bandpassfilter 166 provided by the baseband impedance 162 is shifted to RF (orother desired frequency) creating the high-Q RF bandpass filter 168.

FIG. 38 is a schematic block diagram of another embodiment of a receiverof one or more of the transceivers of FIGS. 1-3 that includes a sampleand hold filter circuit 158, a FTBPF 156, a programmable FIR filter 174,a down conversion module 164, and an analog to digital converter (ADC)176. The receiver may further include a band pass filter (BPF), a lownoise amplifier (LNA), and a clock circuit module as shown in FIG. 4.

In an example of operation, the sample and hold filter 158 receives aninbound RF signal and samples it at a sampling frequency, which isgreater than or equal to two times the bandwidth of the inbound RFsignal up to the carrier frequency of the inbound RF signal. The sampleand hold filter 158 outputs, in the frequency domain, a plurality ofpulses spaced in frequency by the sampling frequency. The sample andhold output includes a pulse at RF, which corresponds to the originalinbound RF signal.

The frequency translation bandpass filter (FTBPF) 156 provides an RFfilter that passes the RF pulse substantially unattenuated andattenuates the other frequency pulses. The programmable FIR filter 174(e.g., as discussed with reference to FIG. 33) filters the RF pulse toproduce a filtered RF signal, which it provides to the down conversionmodule 164. The down conversion module 164 converts the output of theprogrammable FIR 174 to a baseband signal (e.g., an analog symbolstream). The analog to digital converter 176 converts the basebandsignal into a digital signal (e.g., an inbound symbol stream).

In an alternate embodiment, the frequency translated band pass filter(FTBPF) 156 is coupled to the input of the sample and hold circuit 158to function as an RF band pass filter. The programmable FIR filter 174is programmed to pass the baseband frequency pulse of the output of thesample and hold circuit 158 and to attenuate the other frequency pulses.As such, the output of the programmable FIR filter 174 is at baseband,which eliminates the need for the down conversion module 164.

FIG. 39 is a schematic block diagram of another embodiment of a receiverof one or more of the transceivers of FIGS. 1-3 that includes a sampleand hold filter circuit 158, a FTBPF 156, a programmable IIR filter 178,a down conversion module 164, and an analog to digital converter (ADC)176. The receiver may further include a band pass filter (BPF), a lownoise amplifier (LNA), and a clock circuit module as shown in FIG. 4.

In an example of operation, the sample and hold filter 158 receives aninbound RF signal and samples it at a sampling frequency, which isgreater than or equal to two times the bandwidth of the inbound RFsignal up to the carrier frequency of the inbound RF signal. The sampleand hold filter 158 outputs, in the frequency domain, a plurality ofpulses spaced in frequency by the sampling frequency. The sample andhold output includes a pulse at RF, which corresponds to the originalinbound RF signal.

The frequency translation bandpass filter (FTBPF) 156 provides an RFfilter that passes the RF pulse substantially unattenuated andattenuates the other frequency pulses. The programmable IIR filter 178(e.g., as discussed with reference to FIG. 34) filters the RF pulse toproduce a filtered RF signal, which it provides to the down conversionmodule 164. The down conversion module 164 converts the output of theprogrammable IIR 178 to a baseband signal (e.g., an analog symbolstream). The analog to digital converter 176 converts the basebandsignal into a digital signal (e.g., an inbound symbol stream).

In an alternate embodiment, the frequency translated band pass filter(FTBPF) 156 is coupled to the input of the sample and hold circuit 158to function as an RF band pass filter. The programmable IIR filter 178is programmed to pass the baseband frequency pulse of the output of thesample and hold circuit 158 and to attenuate the other frequency pulses.As such, the output of the programmable IIR filter 178 is at baseband,which eliminates the need for the down conversion module 164.

FIG. 40 is a schematic block diagram of an embodiment of an analog todigital converter 180 within a receiver of one or more of thetransceivers of FIGS. 1-3. The receiver includes a band pass filter(BPF) 182, a low noise amplifier (LNA) 184, a sample and hold filtercircuit 186, a discrete time filter 188, a down conversion module 190,an analog to digital converter (ADC) 180, and a clock circuit module(only the analog to digital converter (ADC) clock circuit 192 is shown)that provides an ADC oversampling clock 198. The bandpass filter 182,the low noise amplifier 184, the sample and hold circuit 186, thediscrete time filter 188, and the down conversion module 190 function aspreviously discussed with reference to FIG. 4 and/or other precedingfigures.

The ADC 180 includes a sigma delta modulator 184 and decimation filter196 to convert on analog signal into a digital signal. The sigma deltamodulator 194 and/or the decimation filter 196 may be programmable toadjust the analog to digital conversion based on operating conditions ofthe receiver. For example, for a low data rate wireless communication,the bit resolution of the analog to digital converter 180 may be reduced(e.g., to 8 bits). As another example, for a higher data rate wirelesscommunication, the resolution of the analog to digital converter 180 maybe increased (e.g., 12-16 bits). Note that other embodiments of theanalog to digital converter 180 may be used. For example, the analog todigital converter 180 may have a flash topology, a successiveapproximation topology, or other type of analog to digital conversiontopology.

FIG. 41 is a schematic block diagram of another embodiment of a receiverof one or more of the transceivers of FIGS. 1-3 that includes afrequency translated band pass filter (FTBPF) 200, a low noise amplifier(LNA) 202, a sample and hold filter circuit 204, a discrete time filter206, a down conversion module, 208 an analog to digital converter (ADC)210, and a clock circuit module. The clock circuit module includes aclock generator 212, an FTBPF clock 214, a sample and hold (S&H) clockcircuit 216, a filter clock circuit 218, a local oscillation (LO) clockcircuit 220, and an analog to digital converter (ADC) clock circuit 222.

In an example of operation, the FTBPF 200 filters an inbound RF signalby attenuating out of band signal components and passing, substantiallyunattenuated, in-band signal components (an example of the FTBPF 200 wasdescribed with reference to FIGS. 35-37). The low noise amplifier 202amplifies the in-band signal components of the inbound RF signal toproduce an amplified inbound RF signal.

The sample and hold filter 204 receives the amplified inbound RF signaland samples it in accordance with a sample clock signal and a hold clocksignal. The sample and hold filter 204 outputs, in the frequency domain,a plurality of pulses spaced in frequency by the sampling frequency,which includes a pulse at RF (e.g., the original inbound RF signal).

The discrete time filter 206 (which may be a finite impulse responsefilter, an infinite impulse response filter, a frequency translationbandpass filter, and/or other type of discrete filter) receives theoutput of the sample and hold filter circuit 204 and filters it.Depending on the filtering response of the discrete time filter 206, thediscrete time filter 206 will output, in the frequency domain, a singlepulse of the sample and hold output at a particular frequency. The downconversion module 208 converts the output of the discrete time filter206 to a baseband signal (e.g., an analog symbol stream). The analog todigital converter 210 converts the baseband signal into a digital signal(e.g., an inbound symbol stream.

FIG. 42 is a schematic block diagram of an embodiment of a receiver ofone or more of the transceivers of FIGS. 1-3 that includes a band passfilter (BPF) module 224 a sample and hold filter circuit 204, a discretetime filter 206, and an analog to digital converter (ADC) 210. Thereceiver may further include a low noise amplifier (LNA) 202 and a clockcircuit module. The clock circuit module includes a clock generator 212,a sample and hold (S&H) clock circuit 216, a filter clock circuit 218,and an analog to digital converter (ADC) clock circuit 222.

In an example of operation, the band pass filter 224 receives an inboundRF signal from the antenna interface. The band pass filter 224attenuates out of band signal components and passes, substantiallyunattenuated, in-band signal components of the inbound RF signal. Thebandpass filter module includes a bandpass filter. In an example, thebandpass filter is a frequency translation bandpass filter and thebandpass filter module further includes a buffer module (e.g., one ormore buffers and/or inverters) that is operable to buffer the inboundwireless signal prior to filtering.

The low noise amplifier 202 amplifies the in-band signal components ofthe inbound RF signal to produce an amplified inbound RF signal. Withreference to FIG. 43, an inbound RF signal is shown in the frequencydomain to have in-band signal components centered about an RF carrierfrequency and out of band signal components at the edges of the signal.The output of the low noise amplifier 202 is shown in the time domainand the frequency domain to have the out of band signal componentssubstantially attenuated and, the inbound signal components of theinbound RF signal are substantially unattenuated.

Returning to the discussion of FIG. 42, the sample and hold filter 204receives the amplified inbound RF signal and samples it in accordancewith a sample clock signal and a hold clock signal. With reference toFIG. 44, the sample and hold circuit 204 receives the amplified inboundRF signal (shown in the frequency domain) and samples it at a samplingfrequency (fs). In this example, the sampling frequency is greater thanor equal to two times the bandwidth of the amplified inbound RF signal.In general, the bandwidth of the amplified inbound RF signal correspondsto the bandwidth of the baseband signal component of the inbound RFsignal. For instance, the bandwidth of the baseband inbound signal maybe a few hundred kilohertz to tens of megahertz. The sample and holdfilter 204 outputs, in the frequency domain, a plurality of pulsesspaced in frequency by the sampling frequency, which includes theoriginal inbound RF signal at RF.

Returning to the discussion of FIG. 42, the discrete time filter 206(which may be a finite impulse response filter, an infinite impulseresponse filter, a frequency translation bandpass filter, and/or othertype of discrete filter) receives the output of the sample and holdfilter circuit 204 and filters it to baseband. With reference to FIG.45, the filter response 228 of the discrete digital filter 204 is atbaseband and, as such, its output includes the baseband pulse of thepulse train output of the sample and hold filter circuit 204. The analogto digital converter 210 converts the baseband signal into a digitalsignal (e.g., an inbound symbol stream), which may be process aspreviously described with reference to FIGS. 1-3.

FIG. 46 is a schematic block diagram of another embodiment of a receiverof one or more of the transceivers of FIGS. 1-3 that includes afrequency translated band pass filter (FTBPF) 200, a low noise amplifier(LNA) 202, a sample and hold filter circuit 204, a discrete time filter206, an analog to digital converter (ADC) 210, and a clock circuitmodule. The clock circuit module includes a clock generator 212, anFTBPF clock circuit 214, a sample and hold (S&H) clock circuit 216, afilter clock circuit 218, and an analog to digital converter (ADC) clockcircuit 222.

In an example of operation, the FTBPF 200 filters an inbound RF signalby attenuating out of band signal components and passing, substantiallyunattenuated, in-band signal components of the inbound RF signal. Thelow noise amplifier 202 amplifies the in-band signal components of theinbound RF signal to produce an amplified inbound RF signal. As anexample, the output of the LNA 202 is similar to the output of the LNA202 shown in FIG. 43.

The sample and hold filter 204 receives the amplified inbound RF signaland samples it in accordance with a sample clock signal and a hold clocksignal. With reference to FIG. 44, the sample and hold circuit 204receives the amplified inbound RF signal (shown in the frequency domain)and samples it at a sampling frequency (fs). In this example, thesampling frequency is greater than or equal to two times the bandwidthof the amplified inbound RF signal.

Returning to the discussion of FIG. 46, the discrete time filter 206(which may be a finite impulse response filter, an infinite impulseresponse filter, a frequency translation bandpass filter, and/or othertype of discrete filter) receives the output of the sample and holdfilter circuit 204 and filters it to baseband. With reference to FIG.45, the filter response of the discrete digital filter 206 is atbaseband and, as such, its output includes the baseband pulse of thepulse train output of the sample and hold filter circuit 204. The analogto digital converter 210 converts the baseband signal into a digitalsignal (e.g., an inbound symbol stream), which may be process aspreviously described with reference to FIGS. 1-3.

FIG. 47 is a schematic block diagram of another embodiment of a receiverof one or more of the transceivers of FIGS. 1-3 that includes a sampleand hold filter circuit 204, a discrete time filter 206, and a downconversion module 208. The receiver may further include a low noiseamplifier (LNA) 202, an analog to digital converter (ADC) 210, and aclock circuit module. The clock circuit module includes a clockgenerator 212, a sample and hold (S&H) clock circuit 216, a filter clockcircuit 218, a local oscillation (LO) clock circuit 220, and an analogto digital converter (ADC) clock circuit 222. Note that, in thisembodiment, the receiver may not include an RF BPF or it includes awideband RF BPF (e.g., has a band pass region that covers more than onefrequency band).

In an example of operation, the low noise amplifier 202 amplifies theinbound RF signal to produce an amplified inbound RF signal. Withreference to FIG. 48, an inbound RF signal 226 is shown in the frequencydomain to have in-band signal components centered about an RF carrierfrequency and out of band signal components at the edges of the signal.The output of the low noise amplifier 202 is shown in the time domainand the frequency domain to include the out of band signal componentsand the inbound signal components of the inbound RF signal.

Returning to the discussion of FIG. 47, the sample and hold filter 204receives the amplified inbound RF signal and samples it in accordancewith a sample clock signal and a hold clock signal. With reference toFIG. 49, the sample and hold circuit 204 receives the amplified inboundRF signal (shown in the frequency domain) and samples it at a samplingfrequency (fs). In this example, the sampling frequency is greater thanor equal to two times RF or MMW (e.g., the carrier frequency of theinbound RF or MMW signal). The sample and hold filter 204 outputs, inthe frequency domain, a plurality of pulses spaced in frequency by thesampling frequency. The sample and hold output includes a pulse at RF,which corresponds to the original inbound RF signal 230.

Returning to the discussion of FIG. 47, the discrete time filter 206(which may be a finite impulse response filter, an infinite impulseresponse filter, a frequency translation bandpass filter, and/or othertype of discrete filter) receives the output of the sample and holdfilter circuit 204 and filters it to RF. With reference to FIG. 50, thefilter response 228 of the discrete digital filter 206 is at RF and, assuch, its output includes the RF pulse of the pulse train output of thesample and hold filter circuit 204.

Returning to the discussion of FIG. 47, the down conversion module 208converts the output of the discrete time filter 206, which is at awireless frequency (e.g., the RF or MMW carrier frequency of the inboundwireless signal) to a baseband signal (e.g., an analog symbol stream) asshown in FIG. 51. The analog to digital converter 210 converts thebaseband signal into a digital signal (e.g., an inbound symbol stream),which may be process as previously described with reference to FIGS.1-3.

FIG. 52 is a schematic block diagram of another embodiment of a receiverof one or more of the transceivers of FIGS. 1-3 that includes a bandpass filter (BPF) 224, a low noise amplifier (LNA) 202, a sample andhold filter circuit 204, a discrete time filter 206, and a programmableconversion module, which may include a down conversion module 208, ananalog to digital converter (ADC) 210. The receiver may further includea clock circuit module that includes a clock generator 212, a sample andhold (S&H) clock circuit 216, a filter clock circuit 218, a localoscillation (LO) clock circuit 232-234, and an analog to digitalconverter (ADC) clock circuit 222. The down conversion module 208includes a sample and hold filter 204 and a discrete time filter 206.

In an example of operation, the band pass filter 224 receives an inboundRF signal from the antenna interface. The band pass filter 224attenuates out of band signal components and passes, substantiallyunattenuated, in-band signal components of the inbound RF signal. Thelow noise amplifier 202 amplifies the in-band signal components of theinbound RF signal to produce an amplified inbound RF signal.

The sample and hold filter 204 receives the amplified inbound RF signaland samples it in accordance with a sample clock signal and a hold clocksignal, which are established in accordance with control information(e.g., information to establish sample rate, ratio of sampling toholding, impedance module tuning, etc.). With reference to FIG. 53, thesample and hold circuit 204 receives the amplified inbound RF signal(shown in the frequency domain) and samples it at a sampling frequency(fs). In this example, the sampling frequency is greater than or equalto two times the bandwidth of the amplified inbound RF signal. Thesample and hold filter 204 outputs, in the frequency domain, a pluralityof pulses spaced in frequency by the sampling frequency. The sample andhold output includes a pulse at RF, which corresponds to the originalinbound RF signal.

Returning to the discussion of FIG. 52, the discrete time filter 206(which may be a finite impulse response filter, an infinite impulseresponse filter, a frequency translation bandpass filter, and/or othertype of discrete filter) receives the output of the sample and holdfilter circuit 204 and filters it to an intermediate frequency(IF=RF−n*fs, where n is an integer greater than or equal to 1). Withreference to FIG. 54, the filter response of the discrete digital filter206 is at IF and, as such, its output includes the IF pulse of the pulsetrain output of the sample and hold filter circuit 204.

Returning to the discussion of FIG. 52, the down conversion module 208receives the IF signal from the discrete digital filter 206 via a sampleand hold filter circuit 204. With reference to FIG. 55, the sample andhold circuit 204 receives the IF signal and samples it at a samplingfrequency (fs). In this example, the sampling frequency is greater thanor equal to two times the bandwidth of the IF signal, which may be lessthan or equal to the bandwidth of the inbound RF signal. The sample andhold filter 204 outputs, in the frequency domain, a plurality of pulsesspaced in frequency by the sampling frequency. The sample and holdoutput includes a pulse at IF, which corresponds to its original inputIF signal.

With reference to FIG. 56, the discrete time filter 206 (which may be afinite impulse response filter, an infinite impulse response filter, afrequency translation bandpass filter, and/or other type of discretefilter) receives the output of the sample and hold filter circuit 204 ofthe down conversion module 206 and filters it baseband. As shown, thefilter response 228 of the discrete digital filter 206 is at basebandand, as such, its output includes the baseband pulse of the pulse trainoutput of the sample and hold filter circuit 204. The analog to digitalconverter 210 converts the baseband signal into a digital signal (e.g.,an inbound symbol stream), which may be process as previously describedwith reference to FIGS. 1-3.

FIG. 57 is a schematic block diagram of another embodiment of a receiverof one or more of the transceivers of FIGS. 1-3 that includes a lownoise amplifier (LNA) 202, a sample and hold filter circuit 204, adiscrete time filter 206, a down conversion module 208, an analog todigital converter (ADC) 210, and a clock circuit module. The clockcircuit module includes a clock generator 212, a sample and hold (S&H)clock circuit 216, a filter clock circuit 218, a local oscillation (LO)clock circuit 232-234, and an analog to digital converter (ADC) clockcircuit 222. The down conversion module 208 includes a sample and holdfilter 204 and a discrete time filter 206. Note that, in thisembodiment, the receiver may not include an RF BPF or it includes awideband RF BPF (e.g., has a band pass region that covers more than onefrequency band).

In an example of operation, the low noise amplifier 202 amplifies theinbound RF signal to produce an amplified inbound RF signal. The sampleand hold filter 204 receives the amplified inbound RF signal and samplesit in accordance with a sample clock signal and a hold clock signal.With reference to FIG. 58, the sample and hold circuit 204 receives theamplified inbound RF signal and samples it at a sampling frequency (fs).In this example, the sampling frequency is greater than or equal to twotimes RF (e.g., the carrier frequency of the inbound RF signal). Thesample and hold filter 204 outputs, in the frequency domain, a pluralityof pulses spaced in frequency by the sampling frequency. The sample andhold output includes a pulse at RF, which corresponds to the originalinbound RF signal 230.

Returning to the discussion of FIG. 57, the discrete time filter 206(which may be a finite impulse response filter, an infinite impulseresponse filter, a frequency translation bandpass filter, and/or othertype of discrete filter) receives the output of the sample and holdfilter circuit 204 and filters it to RF. With reference to FIG. 59, thefilter response 228 of the discrete digital filter 206 is at RF and, assuch, its output includes the RF pulse of the pulse train output of thesample and hold filter circuit 204.

Returning to the discussion of FIG. 57, the down conversion module 208receives the IF signal from the discrete digital filter 206 via a sampleand hold filter circuit 204. With reference to FIG. 60, the sample andhold circuit 204 receives the IF signal and samples it at a samplingfrequency (fs). In this example, the sampling frequency is greater thanor equal to two times the bandwidth of the inbound RF signal. The sampleand hold filter 204 outputs, in the frequency domain, a plurality ofpulses spaced in frequency by the sampling frequency. The sample andhold output includes a pulse at RF, which corresponds to its originalinput RF signal.

With reference to FIG. 61, the discrete time filter 206 (which may be afinite impulse response filter, an infinite impulse response filter, afrequency translation bandpass filter, and/or other type of discretefilter) receives the output of the sample and hold filter circuit 204 ofthe down conversion module 208 and filters it baseband. As shown, thefilter response of the discrete digital filter 206 is at baseband and,as such, its output includes the baseband pulse of the pulse trainoutput of the sample and hold filter circuit 204. The analog to digitalconverter 210 converts the baseband signal into a digital signal (e.g.,an inbound symbol stream), which may be process as previously describedwith reference to FIGS. 1-3.

FIG. 62 is a schematic block diagram of another embodiment of a receiverof one or more of the transceivers of FIGS. 1-3 that includes a bandpassfilter 224, a forward RF path, a blocker RF path, a combining module236, a down conversion module 208, an analog to digital converter 210,and a clock generation circuit module. The forward RF path includes alow noise amplifier 202, a sample and hold filter circuit 204, and aband pass frequency discrete time filter 238. The blocker RF pathincludes a low noise amplifier 202, a sample and hold filter circuit204, and a notch discrete time filter 240. The clock circuit moduleincludes a clock generator 212, a forward path sample and hold (S&H)clock circuit 242, a forward path filter clock circuit 248, a blockerpath sample and hold (S&H) clock circuit 246, a blocker path filterclock circuit 250, a local oscillation (LO) clock circuit 220, and ananalog to digital converter (ADC) clock circuit 222.

In an example of operation, the band pass filter 224 receives an inboundRF signal from the antenna interface. The band pass filter 224attenuates out of band signal components and passes, substantiallyunattenuated, in-band signal components of the inbound RF signal toproduce a filtered inbound RF signal. Nevertheless, due to the signalstrength of a blocking signal (e.g., an interfering signal having afrequency close to the frequency of the inbound RF signal, the transmitsignal, or some other undesired signal) component passes through the RFBPF 224. As such, the filtered inbound RF signal includes one or moreblocker components. The RF BPF 224 provides the filtered inbound RFsignal to the forward RF path and the blocker RF path.

The low noise amplifier 202 of the forward RF path amplifies thefiltered inbound RF signal to produce an amplified inbound RF signal.The sample and hold filter 204 of the forward RF path receives theamplified inbound RF signal and samples it in accordance with a sampleclock signal and a hold clock signal. With reference to FIG. 63, theforward path sample and hold circuit 204 receives the amplified inboundRF signal (shown in the frequency domain to include a desired inbound RFsignal component and one or more blockers at f1 and/or at f2) andsamples it at a sampling frequency (fs). In this example, the samplingfrequency is greater than or equal to two times the bandwidth of theamplified inbound RF signal and the potential blockers. In this manner,the blockers, which are too close and too strong to effectively filter,are passed (and may be attenuated). The sample and hold filter 204outputs, in the frequency domain, a plurality of pulses spaced infrequency by the sampling frequency. Each pulse of the frequency pulsetrain includes one or more blocker components and the desired inbound RFcomponent. The sample and hold output includes a pulse at RF, whichcorresponds to the original inbound RF signal.

Returning to the discussion of FIG. 62, the forward path discrete timefilter 238 (which may be a finite impulse response filter, an infiniteimpulse response filter, a frequency translation bandpass filter, and/orother type of discrete filter) receives the output of the forward pathsample and hold filter circuit 204 and filters it to RF. With referenceto FIG. 64, the filter response 228 of the discrete digital filter 238is at RF and has a bandpass region that includes the one or moreblockers. As such, the output of the forward path discrete time filter238 includes the RF pulse (e.g., the desired inbound RF signal componentand the one or more blockers) of the pulse train output of the sampleand hold filter circuit 204.

Returning to the discussion of FIG. 62, the low noise amplifier 202 ofthe blocker RF path amplifies the filtered inbound RF signal to producean amplified inbound RF signal. The sample and hold filter 204 of theblocker RF path receives the amplified inbound RF signal and samples itin accordance with a sample clock signal and a hold clock signal. Withreference to FIG. 65, the blocker path sample and hold circuit 204receives the amplified inbound RF signal (shown in the frequency domainto include a desired inbound RF signal component and one or moreblockers at f1 and/or at f2) and samples it at a sampling frequency(fs). In this example, the sampling frequency is greater than or equalto two times the bandwidth of the amplified inbound RF signal and thepotential blockers. In this manner, the blockers, which are too closeand too strong to effectively filter, are passed (and may beattenuated). The sample and hold filter 204 outputs, in the frequencydomain, a plurality of pulses spaced in frequency by the samplingfrequency. Each pulse of the frequency pulse train includes one or moreblocker components and the desired inbound RF component. The sample andhold output includes a pulse at RF, which corresponds to the originalinbound RF signal.

Returning to the discussion of FIG. 62, the blocker path discrete timefilter 240 (which may be a finite impulse response filter, an infiniteimpulse response filter, a frequency translation bandpass filter, and/orother type of discrete filter) receives the output of the blocker pathsample and hold filter circuit 204 and notch filters it to RF. Withreference to FIG. 66, the filter response 252 of the discrete digitalfilter 240 is a notch filter 240 at RF that attenuates the desiredinbound RF signal component and passes the one or more blockers. Assuch, the output of the blocker path discrete time filter 240 includesthe one or more blockers of the RF pulse of the pulse train.

Returning to the discussion of FIG. 62, the combining module 236combines (e.g., subtracts, etc.) the output of the blocker path discretetime filter 240 from the output of the forward path discrete time filter238. Since the blocker path includes the one or more blocker signalsonly, when it is subtracted from the forward path signal, which includesthe desired inbound RF signal component and the one or more blockers,the resultant is the desired inbound RF signal component.

The down conversion module 208 may be implemented using analog circuitry(e.g., a mixer, a local oscillation, and one or more pass filters) or itmay be implemented as discrete time digital circuitry (e.g., a sampleand hold circuit 204 and a discrete time filter 238-240). Regardless ofthe implementation, the down conversion module 208 converts the outputof the subtraction module 236 to a baseband signal (e.g., an analogsymbol stream). The analog to digital converter 210 converts thebaseband signal into a digital signal (e.g., an inbound symbol stream),which may be process as previously described with reference to FIGS.1-3. Note that, if the output of the combining module is at baseband,then the down conversion module may be omitted and the ADC 210 convertsthe filtered inbound baseband signal into a digital inbound basebandsignal.

FIG. 67 is a schematic block diagram of another embodiment of a receiverof one or more of the transceivers of FIGS. 1-3 that includes a bandpassfilter 224, a low noise amplifier 202, a sample and hold filter circuit204, a band pass frequency discrete time filter 238, a notch discretetime filter 240, a combining module 236, a down conversion module 208,an analog to digital converter 210, and a clock generation circuitmodule. The clock circuit module includes a clock generator 212, asample and hold (S&H) clock circuit 242, a BPF filter clock circuit 248,a notch filter clock circuit 250, a local oscillation (LO) clock circuit220, and an analog to digital converter (ADC) clock circuit 222.

In an example of operation, the band pass filter 224 receives an inboundRF signal from the antenna interface 254. The band pass filter 224attenuates out of band signal components and passes, substantiallyunattenuated, in-band signal components of the inbound RF signal toproduce a filtered inbound RF signal. Nevertheless, due to the signalstrength of a blocking signal (e.g., an interfering signal having afrequency close to the frequency of the inbound RF signal, the transmitsignal, or some other undesired signal) component passes through the RFBPF 224. As such, the filtered inbound RF signal includes one or moreblocker components. The RF BPF 224 provides the filtered inbound RFsignal to the forward RF path and the blocker RF path.

The low noise amplifier 202 amplifies the filtered inbound RF signal toproduce an amplified inbound RF signal. The sample and hold filter 204receives the amplified inbound RF signal and samples it in accordancewith a sample clock signal and a hold clock signal. With reference toFIG. 63, the sample and hold circuit 204 receives the amplified inboundRF signal (shown in the frequency domain to include a desired inbound RFsignal component and one or more blockers at f1 and/or at f2) andsamples it at a sampling frequency (fs) to produce a frequency pulsetrain.

Returning to the discussion of FIG. 67, the BPF discrete time filter 238(which may be a finite impulse response filter, an infinite impulseresponse filter, a frequency translation bandpass filter, and/or othertype of discrete filter) receives the output of the sample and holdfilter circuit 204 and filters it to RF. With reference to FIG. 64, thefilter response 228 of the discrete digital filter 238 is at RF and hasa bandpass region that includes the one or more blockers. As such, theoutput of the forward path discrete time filter 238 includes the RFpulse (e.g., the desired inbound RF signal component and the one or moreblockers) of the pulse train output of the sample and hold filtercircuit 204.

Returning to the discussion of FIG. 67, the notch discrete time filter240 (which may be a finite impulse response filter, an infinite impulseresponse filter, a frequency translation bandpass filter, and/or othertype of discrete filter) receives the output of the sample and holdfilter circuit 204 and notch filters it to RF. With reference to FIG.66, the filter response 252 of the discrete digital filter 240 is anotch filter 240 at RF that attenuates the desired inbound RF signalcomponent and passes the one or more blockers. As such, the output ofthe blocker path discrete time filter 240 includes the one or moreblockers of the RF pulse of the pulse train.

Returning to the discussion of FIG. 67, the combining module 236combines the output of the blocker path discrete time filter 240 fromthe output of the forward path discrete time filter 238. The downconversion module 208 converts the output of the subtraction module 236to a baseband signal (e.g., an analog symbol stream). The analog todigital converter 210 converts the baseband signal into a digital signal(e.g., an inbound symbol stream), which may be process as previouslydescribed with reference to FIGS. 1-3.

FIG. 68 is a schematic block diagram of another embodiment of a receiverof one or more of the transceivers of FIGS. 1-3 that includes a bandpassfilter 224, a low noise amplifier 202, a sample and hold circuit 204, aclock generation circuit, and a plurality of down conversion paths. Eachof the down conversion paths includes a discrete time filter 206, a downconversion module 208, and an analog to digital converter 210. The clockgeneration circuit includes a clock generator 212, a sample and holdclock circuit 242, a plurality of filter clock circuits 218, a pluralityof local oscillation (LO) clock circuits 220, and a plurality of analogto digital converter clock circuits 222.

In an example of operation, the band pass filter 224 receives an inboundRF signal from the antenna interface 254. The band pass filter 224attenuates out of band signal components and passes, substantiallyunattenuated, in-band signal components of the inbound RF signal. Thelow noise amplifier 202 amplifies the in-band signal components of theinbound RF signal to produce an amplified inbound RF signal. Withreference to FIG. 69, an inbound RF signal is shown in the frequencydomain to have in-band signal components centered about an RF carrierfrequency and out of band signal components at the edges of the signal.The output of the low noise amplifier 202 is shown in the frequencydomain to substantially attenuate the out of band signal components andto pass, substantially unattenuated, the inbound signal components ofthe inbound RF signal.

Returning to the discussion of FIG. 68, the sample and hold filter 204receives the amplified inbound RF signal and samples it in accordancewith a sample clock signal and a hold clock signal. With reference toFIG. 70, the sample and hold circuit 204 receives the amplified inboundRF signal and samples it at a sampling frequency (fs). In this example,the sampling frequency is greater than or equal to two times thebandwidth of the amplified inbound RF signal. In general, the bandwidthof the amplified inbound RF signal corresponds to the bandwidth of thebaseband signal component of the inbound RF signal. The sample and holdfilter 224 outputs, in the frequency domain, a plurality of pulsesspaced in frequency by the sampling frequency. The sample and holdoutput includes a pulse at RF, which corresponds to the original inboundRF signal.

Returning to the discussion of FIG. 68, the discrete time filters 206 ofeach down conversion path receives the output of the sample and holdcircuit 204. Each discrete time filter 206 (which may be a finiteimpulse response filter, an infinite impulse response filter, afrequency translation bandpass filter, and/or other type of discretefilter) filters the frequency pulse train (e.g., the output of the S&Hcircuit) in accordance with its filtering response. For example and withreference to FIGS. 71 and 72, if a first discrete time filter 206 has afrequency response of a band pass filter at RF, then it will output theRF pulse of the pulse train and attenuate the other frequency pulses. Ifa second discrete time filter 206 has a frequency response of a bandpass filter at IF (e.g., RF−n*fs, where n is an integer equal to orgreater than 1), then it will output the IF pulse of the pulse train andattenuate the other frequency pulses. With each discrete time filter 206having a band pass filter response at different frequencies, the outputof the sample and hold output is represented by a plurality of differentfiltered frequency pulses.

Returning to the discussion of FIG. 68, each of the down conversionmodule 208 may be implemented using analog circuitry (e.g., a mixer, alocal oscillation, and one or more pass filters) or it may beimplemented as discrete time digital circuitry (e.g., a sample and holdcircuit 204 and a discrete time filter 206). Regardless of theimplementation, the down conversion module 208 of the first pathconverts the output of the first discrete time filter 206 (e.g., the RFfrequency pulse) to a baseband signal (e.g., an analog symbol stream).The analog to digital converter 210 of the first path converts thebaseband signal into a first digital signal (e.g., an inbound symbolstream).

Similarly, the down conversion module 208 of the second path convertsthe output of the second discrete time filter 206 (e.g., the IFfrequency pulse) to a baseband signal (e.g., an analog symbol stream).The analog to digital converter 210 of the second path converts thebaseband signal into a second digital signal (e.g., an inbound symbolstream). As such, a plurality of inbound symbol streams is created fromthe inbound RF signal.

The processing module may process the plurality of inbound symbolstreams in a variety of ways. For example, the processing moduleconverts each of the inbound symbol streams into inbound data, whereinone of the converted inbound data is used as the output. As anotherexample, the processing module combines the first and second inboundbaseband signals using an averaging function to produce the inboundsignal, which it converts into the inbound data. As yet another example,the processing module combines the first and second inbound basebandsignals using a weighted average function to produce the inbound signal,which it converts into the inbound data. As a further example, theprocessing module combines the first and second inbound baseband signalsusing a root mean square function to produce the inbound signal, whichit converts into the inbound data. As a still further example, theprocessing module combines the first and second inbound baseband signalsusing a mathematical function to produce the inbound signal, which itconverts into the inbound data. As an even further example, theprocessing module selects one of the first and second inbound basebandsignals to produce the inbound signal, which it converts into theinbound data. As another further example, the processing module selectsportions from each of the first and second inbound baseband signals toproduce the inbound signal, which it converts into the inbound data. Theportions may be selected based on decoding factors such as signalstrength, accuracy of mapping symbols to bit patterns, etc. As anotherexample, the inbound symbol streams may be compared with one another todetermine accuracy of the receiving process (e.g., conversion of theinbound RF signal into inbound data) and to make corrections thereof.

FIG. 73 is a schematic block diagram of another embodiment of a receiverof one or more of the transceivers of FIGS. 1-3 that includes a bandpassfilter 224, a low noise amplifier 202, a sample and hold circuit 204, aclock generation circuit, and a plurality of down conversion paths. Eachof the down conversion paths includes a discrete time filter 206, a downconversion module 208 (may omit if discrete time filter 206 has abaseband BPF response), and an analog to digital converter 210. Theclock generation circuit includes a clock generator 212, a sample andhold clock circuit 242, a plurality of filter clock circuits 218, aplurality of local oscillation (LO) clock circuits 220, and a pluralityof analog to digital converter clock circuits 222.

In an example of operation, the band pass filter 224 receives an inboundRF signal from the antenna interface 254. The inbound RF signal includesa plurality of channels (or subcarriers), wherein one or more of thechannels includes data of a communication. The band pass filter 224attenuates out of band signal components and passes, substantiallyunattenuated, in-band signal components of the inbound RF signal. Thelow noise amplifier 202 amplifies the in-band signal components of theinbound RF signal to produce an amplified inbound RF signal. Withreference to FIG. 74, an inbound RF signal is shown in the frequencydomain to have in-band signal components centered about an RF carrierfrequency and out of band signal components at the edges of the signal.The output of the low noise amplifier 202 is shown in the frequencydomain to substantially attenuate the out of band signal components andto pass, substantially unattenuated, the inbound signal components ofthe inbound RF signal. In addition, the amplified inbound RF signalincludes a plurality of channels, or sub-carriers of an OFDM basedwireless communication. The gray shaded channels indicate that they arecarrying data and the white shaded channels indicate that they are notcurrently carrying data.

Returning to the discussion of FIG. 73, the sample and hold filter 204receives the amplified inbound RF signal and samples it in accordancewith a sample clock signal and a hold clock signal. With reference toFIG. 75, the sample and hold circuit 204 receives the amplified inboundRF signal and samples it at a sampling frequency (fs). In this example,the sampling frequency is greater than or equal to two times thebandwidth of the amplified inbound RF signal. In general, the bandwidthof the amplified inbound RF signal corresponds to the bandwidth of thebaseband signal component of the inbound RF signal. The sample and holdfilter 204 outputs, in the frequency domain, a plurality of pulses (eachincluding the plurality of channels 256) spaced in frequency by thesampling frequency. The sample and hold output includes a pulse at RF,which corresponds to the original inbound RF signal.

Returning to the discussion of FIG. 73, the discrete time filters 206 ofeach down conversion path receives the output of the sample and holdcircuit 204. Each discrete time filter 205 (which may be a finiteimpulse response filter, an infinite impulse response filter, afrequency translation bandpass filter, and/or other type of discretefilter) filters the frequency pulse train (e.g., the output of the S&Hcircuit 204) in accordance with its filtering response. For example andwith reference to FIGS. 76 and 77, if a first discrete time filter 206has a frequency response of a band pass filter at RF for a specificchannel or channels (or sub-carrier or sub-carriers), then it willoutput the desired channel(s) of the RF pulse of the pulse train andattenuate the other frequency pulses. If a second discrete time filter206 has a frequency response of a band pass filter at IF (e.g., RF−n*fs,where n is an integer equal to or greater than 1) for a specificchannel(s) (or sub-carrier(s)), then it will output the desiredchannel(s) of the IF pulse of the pulse train and attenuate the otherfrequency pulses. With each discrete time filter 206 having a band passfilter response at different frequencies (including the potential ofhaving one at baseband), each channel(s) containing data is representedby a different one of the filtered frequency pulses.

Returning to the discussion of FIG. 73, each of the down conversionmodule 208 may be implemented using analog circuitry (e.g., a mixer, alocal oscillation, and one or more pass filters) or it may beimplemented as discrete time digital circuitry (e.g., a sample and holdcircuit 204 and a discrete time filter 206). Regardless of theimplementation, the down conversion module 208 of the first pathconverts the output of the first discrete time filter 206 (e.g., the RFfrequency pulse) to a baseband signal (e.g., an analog symbol stream ofthe first channel(s)). The analog to digital converter 210 of the firstpath converts the baseband signal into a first digital signal (e.g., aninbound symbol stream).

Similarly, the down conversion module 208 of the second path convertsthe output of the second discrete time filter 206 (e.g., the IFfrequency pulse) to a baseband signal (e.g., an analog symbol stream ofthe second channel(s)). The analog to digital converter 210 of thesecond path converts the baseband signal into a second digital signal(e.g., an inbound symbol stream).

The baseband processing module processes the inbound symbol streams toproduce a plurality of inbound data. The plurality of inbound data maybe part of one communication or part of several communications. As such,the receiver of FIG. 73 can support a single communication that usesmultiple channels and/or support multiple communications using multiplechannels.

FIG. 78 is a schematic block diagram of another embodiment of a receiverof one or more of the transceivers of FIGS. 1-3 that includes a bandpassfilter 224, a first path, a second path, and a clock generation circuit.The first path is coupled to the output of the bandpass filter 224 andincludes a first low noise amplifier 258, a first sample and holdcircuit, 260 a first discrete time filter 262, a first down conversionmodule 264 (may omit if discrete time filter has a baseband BPFresponse), and a first analog to digital converter 266. The second pathis coupled to the input of the bandpass filter 224 and includes a secondlow noise amplifier 268, a second sample and hold circuit 270, a seconddiscrete time filter 272, a second down conversion module 274, and asecond analog to digital converter 276. The clock generation circuitincludes a clock generator 212, first and second sample and hold clockcircuits 278-300, first and second filter clock circuits 302-304, firstand second local oscillation (LO) clock circuits 306-308, and first andsecond analog to digital converter clock circuits 310-312.

In an example of operation, the band pass filter 224 receives an inboundRF signal from the antenna interface. The band pass filter 224attenuates out of band signal components and passes, substantiallyunattenuated, in-band signal components of the inbound RF signal toproduce a filtered inbound RF signal. The unfiltered inbound RF signalis provided to the second path and the filtered inbound RF signal isprovided to the first path.

In the first path, the first low noise amplifier 258 amplifies thein-band signal components of the inbound RF signal to produce anamplified inbound RF signal. The first sample and hold filter 260receives the amplified inbound RF signal and samples it at a samplingrate that is greater than or equal to two times the bandwidth of theamplified inbound RF signal. The first discrete time filter 262 receivesthe output of the sample and hold filter circuit 260 and filters it.Depending on the filtering response of the discrete time filter 262, thediscrete time filter 262 will output, in the frequency domain, a singlepulse of the sample and hold output at a particular frequency (e.g., RF,IF, fs, baseband, etc). If the filter response of the discrete timefilter 262 is at baseband, the first down conversion module 264 may beomitted. If included, the first down conversion module 264 converts theoutput of the discrete time filter 262 to a baseband signal (e.g., ananalog symbol stream). The first analog to digital converter 266converts the baseband signal into a digital signal (e.g., a firstinbound symbol stream).

In the second path, the second low noise amplifier 268 amplifies theunfiltered inbound RF signal to produce a second amplified inbound RFsignal. The second sample and hold filter 270 receives the secondamplified inbound RF signal and samples it at a sampling rate that isgreater than or equal to two times RF (e.g., the carrier frequency ofthe inbound RF signal). The second discrete time filter 272 receives theoutput of the second sample and hold filter circuit 270, filters it atRF, and outputs the frequency pulse at RF. The second down conversionmodule 274 converts the output of the second discrete time filter 272 toa baseband signal (e.g., an analog symbol stream). The second analog todigital converter 276 converts the baseband signal into a second digitalsignal (e.g., a second inbound symbol stream).

Each of the first and second inbound symbol streams may be convertedinto inbound data, wherein one of the converted inbound data is used asthe output. Alternatively, portions of the first and second inboundsymbol streams are selected and the selected portions are converted intothe inbound data. The portions may be selected based on decoding factorssuch as signal strength, accuracy of mapping symbols to bit patterns,etc. As another example, the first and second inbound symbol streams maybe compared with one another to determine accuracy of the receivingprocess (e.g., conversion of the inbound RF signal into inbound data)and to make corrections thereof.

FIG. 79 is a schematic block diagram of another embodiment of a receiverof one or more of the transceivers of FIGS. 1-3 includes a buffer module314 (e.g., an inverter, a buffer, and/or a wide bandwidth unity gainamplifier), a sample and hold filter circuit 204, a discrete time filter206, a down conversion module 208, an analog to digital converter (ADC)210, and a clock circuit module. The clock circuit module includes aclock generator 212, a sample and hold (S&H) clock circuit 216, a filterclock circuit 218, a local oscillation (LO) clock circuit 220, and ananalog to digital converter (ADC) clock circuit 222. Note that, in thisembodiment, the receiver may not include an RF BPF or it includes awideband RF BPF (e.g., has a band pass region that covers more than onefrequency band). Further note that the receiver includes an inverter 314instead of an LNA.

In an example of operation, the inverter 314 receives the inbound RFsignal from the antenna interface and provides it to the sample and holdfilter circuit 204. The inverter 314 has a wider bandwidth than an LNAand, as such, the inbound RF signal may be a wide bandwidth signal(e.g., span more than one frequency band, include multiple frequencieswithin a given frequency band, etc.). The sample and hold filter 204samples inbound RF signal in accordance with a sample clock signal and ahold clock signal, which are clocked in accordance with a samplingfrequency (fs). In this example, the sampling frequency is greater thanor equal to two times RF (e.g., the carrier frequency of the inbound RFsignal). The sample and hold filter 204 outputs, in the frequencydomain, a plurality of pulses spaced in frequency by the samplingfrequency. The sample and hold output includes a pulse at RF, whichcorresponds to the original inbound RF signal.

The discrete time filter 206 (which may be a finite impulse responsefilter, an infinite impulse response filter, a frequency translationbandpass filter, and/or other type of discrete filter) receives theoutput of the sample and hold filter circuit 204 and filters it to RF.In this example, the filter response of the discrete digital filter 206is at RF and, as such, its output includes the RF pulse of the pulsetrain and attenuates the other frequency pulses.

The down conversion module 208 may be implemented using analog circuitry(e.g., a mixer, a local oscillation, and one or more pass filters) or itmay be implemented as discrete time digital circuitry (e.g., a sampleand hold circuit 204 and a discrete time filter 206). Regardless of theimplementation, the down conversion module 208 converts the output ofthe discrete time filter 206 to a baseband signal (e.g., an analogsymbol stream). The analog to digital converter 210 converts thebaseband signal into a digital signal (e.g., an inbound symbol stream),which may be process as previously described with reference to FIGS.1-3.

FIG. 80 is a schematic block diagram of another embodiment of a receiverof one or more of the transceivers of FIGS. 1-3 that includes afrequency translated band pass filter (FTBPF) 200, a buffer module 314(e.g., an inverter, a buffer, and/or a wide bandwidth unity gainamplifier), a sample and hold filter circuit 204, a discrete time filter206, an analog to digital converter (ADC) 210, and a clock circuitmodule. The clock circuit module includes a clock generator 212, anFTBPF clock circuit 316, a sample and hold (S&H) clock circuit 216, afilter clock circuit 318, and an analog to digital converter (ADC) clockcircuit 222.

In an example of operation, the inverter 314 receives the inbound RFsignal from the antenna interface and provides it to the FTBPF 200 andthe sample and hold filter circuit 204. The inverter 314 has a widerbandwidth than an LNA; as such, the inbound RF signal may be a widebandwidth signal (e.g., span more than one frequency band, includemultiple frequencies within a given frequency band, etc.). The FTBPF 200filters an inbound RF signal by attenuating out of band signalcomponents and passing, substantially unattenuated, in-band signalcomponents of the inbound RF signal to produce a filtered inbound RFsignal.

The sample and hold filter 204 receives the filtered inbound RF signaland samples it in accordance with a sample clock signal and a hold clocksignal, which is clocked in accordance with a sampling frequency y (fs).In this example, the sampling frequency is greater than or equal to twotimes the bandwidth of the filtered inbound RF signal.

The discrete time filter 206 receives the output of the sample and holdfilter circuit 204 and filters it to baseband. In this example, thefilter response of the discrete digital filter 206 is at baseband and,as such, its output includes the baseband pulse of the pulse trainoutput of the sample and hold filter circuit 204, with the otherfrequency pulses being attenuated. The analog to digital converter 210converts the baseband signal into a digital signal (e.g., an inboundsymbol stream), which may be process as previously described withreference to FIGS. 1-3.

FIG. 81 is a schematic block diagram of another embodiment of a receiverof one or more of the transceivers of FIGS. 1-3 that includes a buffermodule 314 (e.g., an inverter, a buffer, and/or a wide bandwidth unitygain amplifier), a sample and hold filter circuit 204 a frequencytranslated band pass filter (FTBPF) 200, a down conversion module 208,an analog to digital converter (ADC) 210, and a clock circuit module.The clock circuit module includes a clock generator 212, an FTBPF clockcircuit, a sample and hold (S&H) clock circuit 216, a filter clockcircuit 320, an LO clock circuit 220, and an analog to digital converter(ADC) clock circuit 222.

In an example of operation, the inverter 314 receives the inbound RFsignal from the antenna interface and provides it to the sample and holdfilter circuit 204. The sample and hold filter 204 samples inbound RFsignal in accordance with a sample clock signal and a hold clock signal,which are clocked in accordance with a sampling frequency (fs). In thisexample, the sampling frequency is greater than or equal to two times RF(e.g., the carrier frequency of the inbound RF signal). The sample andhold filter 214 outputs, in the frequency domain, a plurality of pulsesspaced in frequency by the sampling frequency. The sample and holdoutput includes a pulse at RF, which corresponds to the original inboundRF signal.

The FTBPF 200 filters the output of the sample and hold filter circuit204 to RF. In this example, the filter response of the FTBPF 200 is abandpass filter at RF and, as such, its output includes the RF pulse ofthe pulse train and attenuates the other frequency pulses. The downconversion module 208 converts the output of the discrete time filter toa baseband signal (e.g., an analog symbol stream). The analog to digitalconverter 310 converts the baseband signal into a digital signal (e.g.,an inbound symbol stream), which may be process as previously describedwith reference to FIGS. 1-3.

FIG. 82 is a schematic block diagram of an embodiment of a programmablefront end 322 of a receiver of one or more of the transceivers of FIGS.1-3. The programmable front end 322 includes the antenna interface 254,a plurality of switching modules 324, an RF bandpass filter 224, a lownoise amplifier 202, an inverter 314, and a sample and hold circuit 204.The plurality of switching modules 324 (e.g., multiplexers, switches,programmable gates, transistors, etc.) allow for a variety of front endconfigurations. For example, the inbound RF signal (i.e., the output ofthe antenna interface 254) may be directly provided to the sample andhold circuit 204. As another example, the inbound RF signal may bebandpass filtered via the BPF 224 (which may be programmable to adjustthe bandpass region, the center frequency, the attenuation rate, etc.),amplified by the LNA 202, then provided to the sample and hold circuit204.

FIG. 83 is a schematic block diagram of another embodiment of a receiverof one or more of the transceivers of FIGS. 1-3 coupled to the basebandprocessing module 326. The receiver includes a band pass filter (BPF)224, a low noise amplifier (LNA) 202, a sample and hold filter circuit204, sample memory 328, a discrete time filter 206, an analog to digitalconverter (ADC) 310, and a clock circuit module. The clock circuitmodule includes a clock generator 212, a sample and hold (S&H) clockcircuit 216, a filter clock circuit 218, a local oscillation (LO) clockcircuit, and an analog to digital converter (ADC) clock circuit 222.Note that the receiver may also include a down conversion module if thediscrete time filter has a bandpass filter response at RF, IF, or fs.

The baseband processing module 326 is coupled to provide control signalsto one or more of a band pass filter (BPF) 224, a low noise amplifier(LNA) 202, a sample and hold filter circuit 204, the sample memory 328,a discrete time filter 206, an analog to digital converter (ADC) 210,and a clock circuit module to optimize performance of the receiver basedon data recovery feedback 334 (e.g., bit error rate, packet error rate,the data, etc.) and/or receive signal properties 336 (e.g., SNR, signalto interference, RSSI, testing, noise, frequency band of operation,etc.).

The control signals 330 may be used to adjust settings of a component.For example, one or more control signals 330 may be provided to the BPF224 to change the bandpass region, the center frequency, the attenuationrate, etc. As another example, one or more control signals 330 may beprovided to the LNA 202 to change gain, linearity, bandwidth,efficiency, noise, output dynamic range, slew rate, rise rate, settlingtime, overshoot, stability factor, etc. As yet another example, one ormore control signals 330 may be provided to the sample and hold filtercircuit 204 to change the impedances, impedance circuits, etc. As afurther example, one or more control signals 330 may be provided to thediscrete time filter 206 to program it as described with reference toone or more of FIGS. 33-37. As a still further example, the controlsignals may be provided to the sample memory regarding storing samplesand/or retrieving samples. The baseband processing module 326 may alsoprovide one or more control signals 332 to the clock circuits. As anexample, one or more control signals 332 may be provided to the S&Hclock circuit 216 to adjust the sampling frequency, the sampling period,the hold period, etc.

In an example of operation, the band pass filter 224 receives an inboundRF signal from the antenna interface. The band pass filter 224attenuates out of band signal components and passes, substantiallyunattenuated, in-band signal components of the inbound RF signal. Thelow noise amplifier 202 amplifies the in-band signal components of theinbound RF signal to produce an amplified inbound RF signal.

The sample and hold filter 204 receives the amplified inbound RF signaland samples it in accordance with a sample clock signal and a hold clocksignal that are clocked in accordance with a sampling frequency (fs). Inthis example, the sampling frequency is greater than or equal to twotimes the bandwidth of the amplified inbound RF signal.

The sample memory 328 stores the samples outputted by the sample andhold filter circuit 204. The sample memory 328 may store a few samplesto millions of samples in a rolling manner; may take a snapshot of thesamples, etc. The baseband processing module 326 controls the storageand retrieval of the samples to/from the storage memory. In addition,the baseband processing module 326 may utilize the stored samples forreceiver calibration functions, receiver testing functions, and/or errorcorrection. One or more examples will be described with reference toFIGS. 86-90.

The discrete time filter 206 filters samples retrieved from the samplememory 328 based on its filtering response. In this example, the filterresponse of discrete time filter 206 corresponds to a bandpass filter224 at baseband such that the discrete time filter 206 outputs thebaseband frequency pulse and attenuates the other frequency pulses ofthe frequency pulse train of the sample and hold circuit 204. The analogto digital converter 210 converts the baseband signal into a digitalsignal (e.g., an inbound symbol stream).

FIG. 84 is a schematic block diagram of an embodiment of sample memory328 of the receiver of FIG. 83 that includes a digital encoder 338,digital memory 340, and a digital decoder 342. The digital memory 340may be non-volatile or volatile memory random access memory of anyconstruct (e.g., flash, S-RAM, D-RAM, dual data rate, etc.). The digitalencoder 338 (e.g., a flash ADC, a thermometer ADC, etc.) converts theanalog sample value (e.g., magnitude) of a sample into a digital value.The digital decoder 342 performs the inverse function of the digitalencoder 338 (e.g., converts the digital value back into an analog samplevalue).

FIG. 85 is a schematic block diagram of another embodiment of samplememory 328 of the receiver of FIG. 83 that includes a row & columnselect module 344, an input module 346, an output module 348, and aplurality of sample and hold cells 350. Each of the sample and holdcells 350 may be conventional sample and hold circuits and are arrangedinto rows and columns. Each cell 350 is individually accessible forstoring or retrieving a sample value via the row and column selectmodule 244. Alternatively or in addition, the cells 350 may also beaccessible in a group (e.g., a row of cells, a column of cells, a blockof cells, etc.).

In an example of operation, the row & select module 344 selects a cell350 to receive a sample value (e.g., an analog voltage). The inputmodule 346 receives the sample from the sample and hold circuit andprovides it to the selected cell 350 for storage therein. The row &column select module 344 tracks the storage location of each samplevalue in a memory table, which the baseband processing module mayaccess. To retrieve a stored sample value, the row & column selectmodule 344 selects the appropriate cells 350. The output module 348couples to the selected cell 350 and outputs the retrieved sample value.By buffering the samples using a sample memory 328, the basebandprocessing module may be able to correct bit errors, correct packeterrors, better calibrate the receiver, etc.

FIG. 86 is a diagram of an example of the functional operation of atransmitter 352. In general, a transmitter converts outbound data intooutbound RF signals 358, which is done in a sequential manner. Forexample, the outbound data is divided into data words of 2 to 16 bits354 per word, where each word is serially converted into a symbol 356 inaccordance with a data mapping protocol (e.g., QPSK, BPSK, QAM, FSK,ASK, etc.). An RF transmitter section converts each symbol 356 into anRF signal 358 (or a portion thereof), which is transmitted for a givenperiod of time 360 (e.g., nanoseconds to milliseconds).

As shown, while one data word 354 is being converted into a symbol 356the next data word 354 is being prepared for conversion into a symbol356; similarly, as one symbol 356 is being converted into an RF signal358 the next symbol 356 is being prepared for the same conversion. Assuch, every stage of a transmitter (e.g., the baseband processing, theup conversion, etc.) is continually active performing its correspondingfunction.

FIG. 87 is a diagram of an example of the functional operation of areceiver 362 that includes a sample and hold filter circuit. In general,a receiver converts inbound RF signals 358 into inbound data in asequential manner. For example, an inbound signal 358, which correspondsto a symbol 356, is sampled to produce samples 364. The samples 364 aresubsequently converted into a symbol 356, which is then converted intobits 354 (e.g., a data word) in accordance with a data demappingprotocol.

As shown, while one inbound RF signal 358 is being sampled, anotherinbound RF signal 358 is being received and readied for sampling.Similarly, as one set of samples 364 is being converted into a symbol356, another set of samples 364 is being created from an inbound RFsignal 358; and as one symbol 356 is being converted into bits 354,another set of samples 364 is being converted into a symbol 356. In thismanner, every stage of a receiver (e.g., the RF front end, the downconversion process, and the baseband processing) is active performingits corresponding function. As long as inbound RF signals 358 areaccurately converted into bits 354, the pipelined process of thereceiver continues as described. If, however, an inaccuracy occurs inconverting an RF signal 358 into bits 354, the bits 354 are lost.

FIG. 88 is a diagram of an example of the functional operation of areceiver 366 that includes a sample and hold filter circuit and samplememory. In this example, the RF signals 358 are converted into samples364 as previously discussed with reference to FIG. 87 but are bufferedin the sample memory prior to conversion into symbols 356. At a desiredrate, the symbols 356 are retrieved from the buffer 368 and subsequentlyconverted into bits 354. The amount of buffering, overflow threshold,underflow threshold, etc. of the buffer 368 is programmable by thebaseband processing module.

FIG. 89 is a diagram of an example of the functional operation of areceiver 370 that includes a sample and hold filter circuit and samplememory correcting a bit error. In this example, the symbols 356 are thebuffered in the system memory and retrieved sequentially. The firstsymbol 356 retrieved from the buffer 368 encountered an error whenconverting into the desired bits 354. The error may be caused by anumber of factors including, but not limited to, low signal-to-noiseratio, errors in approximations, etc.

When the error is detected and prior to retrieving the next symbol 356,the present symbol 356 is decoded again using a different set ofdecoding factors. The decoding factors include a de-mapping protocol,de-puncturing protocol, decoding protocol, maximum likelihoodestimations, and/or any other variable in converting a symbol 356 intobits 354. With the decoding factors adjusted, the symbol 356 is againconverted into bits 354. If the conversion is successful, the nextsymbol 356 is retrieved and decoded to produce the next set of bits 354.If, however, the conversion was not successful, it is tried again untilthe symbol 356 is properly decoded, an exhaustion factor is reached, orsome other indication to cease decoding the symbol 356 is triggered.Note that once samples have been correctly decoded, the processingmodule may issue a delete command to the sample memory.

FIG. 90 is a logic diagram of an example method that may be performed bya baseband processing module. The method begins by setting parametersfor the sample and hold and the parameters for the discrete time filter372. The sample and hold parameters include sampling period, samplinginterval, sampling frequency, impedance values, impedance circuitsettings, etc. The discrete time filter parameters include coefficients,delay line settings, number of stages, etc.

The method continues by receiving an RF signal 374, which may be aninbound RF communication signal, a test signal, and/or a calibrationsignal. The method continues by converting the RF signal into one ormore symbols 376. The method then continues by converting the symbolsinto data 378. Note that this step may be skipped if the testing of thesample and hold circuits and discrete time filter can be done byanalyzing the symbols, which may be done by a correlation technique, amatching technique, etc.

The method continues by obtaining (e.g., receiving, generating, lookingup, etc.) data recovery feedback and/or receive signal properties 380.The data recovery feedback includes a bit error rate, a packet errorrate, decoding information such as a mapping protocol, etc. The receivesignal properties include received signal strength indication (RSSI),signal-to-noise ratio (SNR), signal to interference ratio, etc.

The method continues by determining whether the information (e.g., thedata recovery feedback and/or the receive signal properties) comparesfavorably to a threshold level (e.g., given the current settings, is thereceiver operating at an acceptable level, an optimal level, and/orbelow the acceptable level, etc.) 382. If the information comparesfavorably to the threshold level, the process repeats by receiving andother RF signal 374.

If, however, the information compares unfavorably to the thresholdlevel, the process continues by determining whether the unfavorablecomparison is at least partially attributable to the sample and holdcircuit and or to the discrete time filter 384. If not, the methodcontinues by adjusting one or more receiver baseband processing settings386. Having made such an adjustment, the method repeats by receivinganother RF signal. If, however, the unfavorable comparison is at leastpartially attributable to the sample and hold circuit and/or thediscrete time filter, the method continues by adjusting a sampling holdparameter and/or a discrete time filter parameter 388. For example, ifthe signal-to-noise ratio is too low, the discrete time filter and/orthe sampling hold filter circuit may be adjusted to improve thefiltering of the inbound RF signal. In this manner, the signal-to-noiseratio might be increased. Having made an adjustment to the S&Hparameters and/or the discrete time filter parameters, the methodrepeats by receiving another RF signal.

FIG. 91 is a schematic block diagram of another embodiment of a receiver390 of one or more of the transceivers of FIGS. 1-3 that includes aplurality of paths and a clock generation circuit. Each path includes alow noise amplifier 202, a sample and hold circuit 204, a discrete timefilter 392, a down conversion module (not shown since it may omit ifdiscrete time filter has a baseband BPF response), and an analog todigital converter 210. The clock generation circuit includes a clockgenerator 212, a plurality of sample and hold clock circuits 242, aplurality of filter clock circuits 394, and a plurality of analog todigital converter clock circuits 222. The clock generator 212 generatesa plurality of phase shifted clock signals; each phase shifted clocksignal clocks a corresponding one of the plurality of paths. As such,for a sampling period, the inbound RF signal is sampled a plurality oftimes (one time for each phase shifted clock). Accordingly, the inboundRF signal is oversampled, which provides options for optimizing the datarecovery process. Note that the plurality of discrete time filtermodules and the plurality of conversion modules (e.g., ADCs or ADCs anddown conversion modules) may be included in a receiver circuit of thereceiver.

In an example of operation of each path, the band pass filter 224receives an inbound RF signal from the antenna interface 254. The bandpass filter 224 attenuates out of band signal components and passes,substantially unattenuated, in-band signal components of the inbound RFsignal. The low noise amplifier 202 amplifies the in-band signalcomponents of the inbound RF signal to produce an amplified inbound RFsignal.

The sample and hold filter 204 receives the amplified inbound RF signaland samples it in accordance with a sample frequency that corresponds tothe respective phase shifted clock signal. In this example, the samplingfrequency is greater than or equal to two times the bandwidth of theamplified inbound RF signal. The discrete time filter 392 (which may bea finite impulse response filter, an infinite impulse response filter, afrequency translation bandpass filter, and/or other type of discretefilter) receives the output of the sample and hold filter circuit 204and filters it to baseband. The analog to digital converter 210 convertsthe baseband signal into a digital signal (e.g., an inbound symbolstream) to produce a plurality of inbound symbol streams.

Each of the plurality of inbound symbol streams may be converted intoinbound data, wherein one of the converted inbound data is used as theoutput. Alternatively, portions of the plurality of inbound symbolstreams are selected and the selected portions are converted into theinbound data. The portions may be selected based on decoding factorssuch as signal strength, accuracy of mapping symbols to bit patterns,etc. As another example, the plurality of inbound symbol streams may becompared with one another to determine accuracy of the receiving process(e.g., conversion of the inbound RF signal into inbound data) and tomake corrections thereof.

FIGS. 92-94 are diagrams of an example of sampling and holding aninbound signal, in the time domain, at a given sampling period (T_(s))and a holding period (T_(h)) that are derived from a correspondingphase-shifted clock signal. The inbound signal g(t) is sampled at agiven sampling interval (Ts) at phase 0 (FIG. 92), at phase 1 (FIG. 93),and at phase n (FIG. 94), where n is an integer greater than or equal to2. The respective holding periods (Th) are shown to be less than thephase offset between phase shifted clock signals, however, the holdingperiods could be equal to or greater than the phase offset.

FIG. 95 is a schematic block diagram of another embodiment of a receiver390 of one or more of the transceivers of FIGS. 1-3 that includes aplurality of bandpass filters (BPF) 224, a plurality of low noiseamplifiers 202, a plurality of sample and hold filter circuits 204, anda receive circuit that may include one or more of a frequencytranslation filter 392 and an analog to digital conversion module 210.The receiver may further include a clock generation circuit, whichincludes a clock generator 212, a plurality of sample and hold clockcircuits 242, a filter clock circuit 394, and an analog to digitalconverter clock circuit 222. The clock generator 212 generates aplurality of phase shifted clock signals; each phase shifted clocksignal clocks a corresponding one of the plurality of S&H clock circuits242. As such, for a sampling period, the inbound RF signal is sampled aplurality of times (one time for each phase shifted clock). Accordingly,the inbound RF signal is oversampled, which provides options foroptimizing the data recovery process.

In an example of operation of each band pass filters 224 receive theinbound RF signal from the antenna interface 254. Each of the band passfilters 224 attenuates out of band signal components and passes,substantially unattenuated, in-band signal components of the inbound RFsignal. Each of the low noise amplifiers 202 amplifies the in-bandsignal components of the inbound RF signal to produce an amplifiedinbound RF signal.

Each of the sample and hold filter 204 receives the correspondingamplified inbound RF signal and samples it in accordance with a samplefrequency that corresponds to the respective phase shifted clock signal.In this example, the sampling frequency is greater than or equal to twotimes the bandwidth of the amplified inbound RF signal. In this manner,the plurality of sample and hold filter circuits 204 generates aplurality of samples for each sampling period.

The frequency translation filter 392 (which may be a finite impulseresponse filter, an infinite impulse response filter, a frequencytranslation bandpass filter, and/or other type of discrete filter)receives the plurality of samples filters them to baseband. Theplurality of samples may be provided to the filter in a sequentialmanner, in a serial manner, or in a combination thereof. The analog todigital converter 210 converts the baseband signal into a digital signal(e.g., an inbound symbol stream) to produce a plurality of inboundsymbol streams.

FIG. 96 is a schematic block diagram of another embodiment of a receiver390 of one or more of the transceivers of FIGS. 1-3 that includes aplurality of bandpass filters (BPF) 224, a plurality of low noiseamplifiers 202, a plurality of sample and hold filter circuits 204, anda receive circuit that may include one or more of a sample processingmodule 396, a frequency translation filter 392, an analog to digitalconversion module 210. The receiver may further include a clockgeneration circuit, which includes a clock generator 212, a plurality ofsample and hold clock circuits 242, a filter clock circuit 394, and ananalog to digital converter clock circuit 222. The clock generator 212generates a plurality of phase shifted clock signals; each phase shiftedclock signal clocks a corresponding one of the plurality of S&H clockcircuits 204. As such, for a sampling period, the inbound RF signal issampled a plurality of times (one time for each phase shifted clock).Accordingly, the inbound RF signal is oversampled, which providesoptions for optimizing the data recovery process.

In an example of operation of each band pass filter 224 receives theinbound RF signal from the antenna interface 254. Each of the band passfilters 224 attenuates out of band signal components and passes,substantially unattenuated, in-band signal components of the inbound RFsignal. Each of the low noise amplifiers 202 amplifies the in-bandsignal components of the inbound RF signal to produce an amplifiedinbound RF signal.

Each of the sample and hold filter 204 receives the correspondingamplified inbound RF signal and samples it in accordance with a samplefrequency that corresponds to the respective phase shifted clock signal.In this example, the sampling frequency is greater than or equal to twotimes the bandwidth of the amplified inbound RF signal. In this manner,the plurality of sample and hold filter circuits 204 generates aplurality of samples for each sampling period.

The sample processing module 396 receives, for a given sampling period,the plurality of samples and processes them to produce a processedsample. The processing may be to average the sample values, perform aroot mean square on the sample values, to perform a weighted average onthe sample values, or some other mathematical function on the samplevalues to produce a representative sample value. The sample processingmodule 396 provides the processed samples to the frequency translationfilter.

The frequency translation filter 392 (which may be a finite impulseresponse filter, an infinite impulse response filter, a frequencytranslation bandpass filter, and/or other type of discrete filter)filters the processed samples to produce an analog baseband signal. Theanalog to digital converter 210 converts the baseband signal into adigital signal (e.g., an inbound symbol stream) to produce a pluralityof inbound symbol streams.

FIG. 97 is a schematic block diagram of another embodiment of a receiver398 of one or more of the transceivers of FIGS. 1-3 that is coupled to aplurality of antenna interfaces 254 (two shown) for multiplecommunications (e.g., different standards). The receiver 398 includes asample and hold filter circuit 204, a discrete time filter 392, a downconversion module 208, an analog to digital conversion module (ADC) 210,and a clock circuit module. The clock circuit module includes a clockgenerator 212, a sample and hold (S&H) clock circuit 242, a filter clockcircuit 394, a local oscillation (LO) clock circuit 220, and an analogto digital converter (ADC) clock circuit 222. Note that the receiver mayfurther include a plurality of band pass filters (BPF) and/or aplurality of low noise amplifiers (LNA).

In an example of operation, if the receiver 398 includes band passfilters, they each receive an inbound RF signal from a corresponding oneof the antenna interfaces 254. For example, a first BPF receives a firstinbound RF signal that is in accordance with a first wirelesscommunication standard and a second BPF receives a second inbound RFsignal that is in accordance with a second wireless communicationstandard. As a further example, the first inbound RF signal may be in afirst frequency band and the second inbound RF signal may be in a secondfrequency band. Each of the band pass filters attenuates out of bandsignal components and passes, substantially unattenuated, in-band signalcomponents of the respective inbound RF signal. The low noise amplifieramplifies the in-band signal components of the inbound RF signal toproduce an amplified inbound RF signal.

The sample and hold filter 204 receives the amplified inbound RF signalsand samples them in accordance with a sample clock signal and a holdclock signal. With reference to FIG. 98, the sample and hold circuit 204receives the amplified inbound RF signals (shown in the frequencydomain) and samples them at a sampling frequency (fs). The samplingfrequency may be equal to or greater than 2*RF2 (e.g., the highercarrier frequency of the two inbound RF signals); may be equal to orgreater than 2*BW1&2 (e.g., a frequency region that spans both inboundRF signals); or the sampling frequency may be toggled between 2*BW1 and2*BW2.

In this example, the sampling frequency is greater than or equal to twotimes RF2 (e.g., the higher carrier frequency of the two inbound RFsignals). At this sampling rate, the sample and hold circuit 204generates an output 404 as shown in FIG. 99. As shown, the S&H outputincludes a pair of pulses (one for the first inbound signal and theother for the second inbound signal) at the sampling frequency andmultiples thereof. The bold pulses at RF1 and RF2 represent the originalinbound RF signal 400.

Returning to the discussion of FIG. 97, the discrete time filter 392(which may be one or more finite impulse response filters, one or moreinfinite impulse response filters, and/or one or more frequencytranslation bandpass filters) receives the output of the sample and holdfilter circuit 204 and filters it. Depending on the filtering responseof the discrete time filter 392, the discrete time filter 392 willoutput, in the frequency domain, a pair of pulses of the sample and holdoutput 400 at a particular frequency pair. For example and as shown inFIG. 100, if the filtering response 402 of the discrete time filter 392corresponds to a bandpass filters centered at RF1 and RF2, the discretetime filter 392 will output the pulses at RF1 and RF2 and attenuate thepulses at the other frequencies. As another example, if the filterresponse of discrete time filter 392 corresponds to a bandpass filtercentered at a pair of intermediate frequencies (e.g., n*fs), thediscrete time filter 392 will output the pulses at the intermediatefrequencies and attenuate the pulses at the other frequencies.

The down conversion module 208 may be implemented using one or moreanalog down conversion circuits (e.g., a mixer, a local oscillation, andone or more pass filters) and/or one or more discrete time digital downconversion circuits (e.g., a sample and hold circuit and a discrete timefilter). Regardless of the implementation, the down conversion module208 converts the output of the discrete time filter 392 to two basebandsignals (e.g., two analog symbol streams). The analog to digitalconversion module 210 (which includes one or more analog to digitalconverters) converts the baseband signals into digital signals (e.g., afirst inbound symbol stream and a second inbound symbol stream), each ofwhich may be process as previously described with reference to FIGS.1-3.

FIG. 101 is a schematic block diagram of another embodiment of areceiver 398 of one or more of the transceivers of FIGS. 1-3 that iscoupled to a plurality of antenna interfaces 254 (two shown) formultiple communications (e.g., different standards). The receiver 398includes a sample and hold filter circuit 204, a frequency translationfilter 392, an analog to digital conversion module (ADC) 210, and aclock circuit module. The clock circuit module includes a clockgenerator 212, a sample and hold (S&H) clock circuit 242, a filter clockcircuit 394, and an analog to digital converter (ADC) clock circuit 222.Note that the receiver 398 may further include a plurality of band passfilters (BPF) and/or a plurality of low noise amplifiers (LNA).

In an example of operation, if the receiver 398 includes band passfilters, they each receive an inbound RF signal from a corresponding oneof the antenna interfaces 254. For example, a first BPF receives a firstinbound RF signal that is in accordance with a first wirelesscommunication standard and a second BPF receives a second inbound RFsignal that is in accordance with a second wireless communicationstandard. As a further example, the first inbound RF signal may be in afirst frequency band and the second inbound RF signal may be in a secondfrequency band. Each of the band pass filters attenuates out of bandsignal components and passes, substantially unattenuated, in-band signalcomponents of the respective inbound RF signal. The low noise amplifieramplifies the in-band signal components of the inbound RF signal toproduce an amplified inbound RF signal.

The sample and hold filter 204 receives the amplified inbound RF signalsand samples them in accordance with a sample clock signal and a holdclock signal. With reference to FIG. 102, the sample and hold circuit202 receives the amplified inbound RF signals (shown in the frequencydomain) and samples them at a sampling frequency (fs). In this example,the sampling frequency is equal to or greater than 2*BW1&2 (e.g., afrequency region that spans both inbound RF signals), where BW1&2 isapproximately equal to n*[(RF1+RF2)/RF1*RF2] and n is an integer equalto or greater than 2 (as shown, n=3). At this sampling rate, the sampleand hold circuit 204 generates an output 402 as shown in FIG. 103. Asshown, the S&H output 402 includes a pair of pulses (one for the firstinbound signal and the other for the second inbound signal) at thesampling frequency and multiples thereof. The bold pulses at RF1 and RF2represent the original inbound RF signal.

Returning to the discussion of FIG. 101, the frequency translationfilter 392 (which may be one or more finite impulse response filters,one or more infinite impulse response filters, and/or one or morefrequency translation bandpass filters) receives the output of thesample and hold filter circuit 204 and filters it. Depending on thefiltering response of the frequency translation filter 392, thefrequency translation filter 392 will output, in the frequency domain, apair of pulses of the sample and hold output 402 at a particularfrequency pair. For example and as shown in FIG. 104, if the filteringresponse 404 of the frequency translation filter 392 corresponds to abandpass filters centered at RF1 and RF2, the discrete time filter willoutput the pulses at RF1 and RF2 and attenuate the pulses at the otherfrequencies. For this example, a down conversion module (as shown inFIG. 97) would be needed to convert the RF signals to baseband signals.

As another example, if the filter response of the frequency translationfilter 392 corresponds to a bandpass filter at baseband, the frequencytranslation filter 392 will output the pulses at the baseband andattenuate the pulses at the other frequencies. FIG. 105 illustrates anexample of the output 406 of the frequency translation filter 392 toinclude a first baseband signal and a second baseband signal.

The analog to digital conversion module 210 (which includes one or moreanalog to digital converters) converts the baseband signals into digitalsignals (e.g., a first inbound symbol stream and a second inbound symbolstream). Each of the inbound symbol streams may be process as previouslydescribed with reference to FIGS. 1-3.

As another example of operation, the receiver of FIG. 97 and/or 101 mayuse a sampling frequency that is toggled between 2*BW1 and 2*BW2. Thefront-end of the receiver functions as previously discussed to input twoinbound RF signals to the sample and hold circuit 204. An example of thesample and hold input 408 is shown in FIG. 106. In this example, thesample and hold filter circuit 204 generates two outputs 410 and 412 asshown in FIGS. 107 and 108. For example, the sample and hold filtercircuit 204 takes one or more samples of the first inbound RF signal atthe sample frequency of 2*BW1, which are outputted via the first output410. The sample and hold filter circuit 204 is then adjusted to take oneor more samples of the second inbound RF signal at the sample frequencyof 2*BW2, which are outputted via the second output 412. The sample andhold filter circuit 204 toggles in this manner as long as two inbound RFsignals are being received or until it is reconfigured for another modeof operation.

FIG. 109 is a schematic block diagram of another embodiment of a sampleand hold circuit 204 that includes a plurality of inputs and a pluralityof outputs. The sample and hold circuit 204 includes a plurality ofsample switching modules 414, a sample element, a plurality of holdswitching modules 416, and a plurality of hold elements. The sampleelement and the hold elements may each be impedances as shown in FIGS.19-22 and/or impedance circuits as shown in FIGS. 23-26. Each of thesample switching modules 414 and the hold switching modules 416 mayinclude a switch and a driver.

In an example of operation, a first input signal is coupled to a firstsample switching module 414 and a second input signal is coupled to asecond sample switching module 414. The first sample switching module414 is clocked in accordance with a first sampling period of a firstsample frequency and the second sample switching module 414 is clockedin accordance with a second sampling period of a second samplefrequency.

When the first sample switching module 414 is active, it drives thefirst input signal on to the sample element, which imposes the magnitudeof the first input signal on the sample element for temporary storagethereon. After the first sample switching modules 414 opens and beforeit closes again for the next sample of the first input signal and beforethe second input signal is sampled, the first hold switching module 416is closed. With the hold switching module 416 closed, it imposes thevoltage on the sample element on to the first hold element. The voltageon the first hold element may be read at any time after the holdswitching module 416 is closed and the voltage on the hold element issubstantially stable.

When the second sample switching module 414 is active, it drives thesecond input signal on to the sample element, which imposes themagnitude of the second input signal on the sample element. After thesecond sample switching modules 414 opens and before it closes again forthe next sample of the second input signal and before the first inputsignal is sampled, the second hold switching module 416 is closed. Withthe second hold switching module 416 closed, it imposes the voltage onthe sample element on to the second hold element. The voltage on thesecond hold element may be read at any time after the second holdswitching module 4116 is closed and the voltage on the hold element issubstantially stable. Note that sample and hold module may have a firstfilter response that is based on a ratio between the first samplingclock signal and the first holding clock signal and a second filterresponse that is based on a ratio between the second sampling clocksignal and the second holding clock signal.

FIG. 109A is a schematic block diagram of another embodiment of a sampleand hold circuit 204 that includes a plurality of inputs and a pluralityof outputs. The sample and hold circuit 204 includes a plurality ofsample switching modules 414, a sample element, and a plurality of holdswitching modules 416. The sample element may each be impedances asshown in FIGS. 19-22 and/or impedance circuits as shown in FIGS. 23-26.Each of the sample switching modules 414 and the hold switching modules416 may include a switch and a driver.

In an example of operation, a first input signal is coupled to a firstsample switching module 414 and a second input signal is coupled to asecond sample switching module 414. The first sample switching module414 is clocked in accordance with a first sampling period of a firstsample frequency and the second sample switching module 414 is clockedin accordance with a second sampling period of a second samplefrequency.

When the first sample switching module 414 is active, it drives thefirst input signal on to the sample element, which imposes the magnitudeof the first input signal on the sample element. After the first sampleswitching modules 414 opens and before it closes again for the nextsample of the first input signal and before the second input signal issampled, the first hold switching module 416 is closed. With the holdswitching module 416 closed, it outputs the voltage on the sampleelement.

When the second sample switching module 414 is active, it drives thesecond input signal on to the sample element, which imposes themagnitude of the second input signal on the sample element. After thesecond sample switching modules 414 opens and before it closes again forthe next sample of the second input signal and before the first inputsignal is sampled, the second hold switching module is closed. With thesecond hold switching module 416 closed, it outputs the voltage on thesample element.

FIG. 110 is a schematic block diagram of another embodiment of a sampleand hold circuit 204 that includes an input and a plurality of outputs.The sample and hold circuit 204 includes a input module 420 (e.g., amultiplexer, a switching circuit, etc.) and a plurality of sample andhold filter circuits 418 (e.g., as shown in FIGS. 19-26). In an exampleof operation, one of the sample and hold filter circuits 204 samples afirst inbound RF signal and another one of the sample and hold filtercircuits 204 samples a second inbound RF signal. The input module 420provides the correct inbound RF signal to the corresponding sample andhold filter circuit 418.

FIG. 111 is a schematic block diagram of another embodiment of areceiver 422 of one or more of the transceivers of FIGS. 1-3 that iscoupled to a plurality of antenna interfaces 254 (two shown) for MIMOcommunications. The receiver 422 includes a sample and hold filtercircuit 204, a discrete time filter 392, a down conversion module 208,an analog to digital conversion module (ADC) 210, and a clock circuitmodule. The clock circuit module includes a clock generator 212, asample and hold (S&H) clock circuit 242, a filter clock circuit 394, alocal oscillation (LO) clock circuit 220, and an analog to digitalconverter (ADC) clock circuit 222. Note that the receiver 422 mayfurther include a plurality of band pass filters (BPF) and/or aplurality of low noise amplifiers (LNA).

In an example of operation, if the receiver 422 includes band passfilters, they each receive an inbound RF signal from a corresponding oneof the antenna interfaces 254. For example, a first BPF receives a firstinbound RF signal of the MIMO communication and a second BPF receives asecond inbound RF signal the MIMO communication, where the first andsecond inbound RF signals are in the same frequency band. Each of theband pass filters attenuates out of band signal components and passes,substantially unattenuated, in-band signal components of the respectiveinbound RF signal. The low noise amplifier amplifies the in-band signalcomponents of the inbound RF signal to produce an amplified inbound RFsignal.

The sample and hold filter 204 receives the amplified inbound RF signalsand samples them in accordance with a sample clock signal and a holdclock signal. With reference to FIG. 112, the sample and hold circuit204 receives the amplified inbound RF signals 424 (shown in thefrequency domain) and samples them at a sampling frequency (fs). Thesampling frequency may be equal to or greater than 2*RF or it may betoggled at 2*BW for each inbound RF signal.

In this example, the sampling frequency is greater than or equal to twotimes BW and is toggled for each inbound RF signal. At this samplingrate, the sample and hold circuit 204 generates outputs 426-428 as shownin FIGS. 113 and 114. As shown, each S&H output 426-428 includes a pulseat the sampling frequency and multiples thereof. The pulse at RFrepresents the original inbound RF signal.

Returning to the discussion of FIG. 11, the discrete time filter 392(which may be one or more finite impulse response filters, one or moreinfinite impulse response filters, and/or one or more frequencytranslation bandpass filters) receives the output of the sample and holdfilter circuit 204 and filters it. Depending on the filtering responseof the discrete time filter 392, the discrete time filter 392 willoutput, in the frequency domain, a pair of pulses of the sample and holdoutput at a particular frequency pair. For example, if the filteringresponse of the discrete time filter 392 corresponds to a bandpassfilters centered at RF, the discrete time filter will output the pulseat RF and attenuate the pulses at the other frequencies for each inboundRF signal. As another example, if the filter response of discrete timefilter 392 corresponds to a bandpass filter centered at an intermediatefrequency (e.g., n*fs), the discrete time filter will output the pulseat the intermediate frequency and attenuate the pulses at the otherfrequencies for each inbound RF signal.

The down conversion module 208 may be implemented using one or moreanalog down conversion circuits 210 (e.g., a mixer, a local oscillation,and one or more pass filters) and/or one or more discrete time digitaldown conversion circuits 208 (e.g., a sample and hold circuit and adiscrete time filter). Regardless of the implementation, the downconversion module 208 converts the output of the discrete time filter392 to two baseband signals (e.g., two analog symbol streams). Theanalog to digital conversion module 210 (which includes one or moreanalog to digital converters) converts the baseband signals into digitalsignals (e.g., a first inbound symbol stream and a second inbound symbolstream), which are processed as previously discussed to retrieve inbounddata.

FIG. 115 is a schematic block diagram of another embodiment of atransmitter 430 of one or more of the transceivers of FIGS. 1-3 thatincludes a clock generation circuit 444, a conversion module (which mayinclude a digital to analog conversion module 432 and/or anup-conversion module 434), a sample and hold filter circuit 436, adiscrete time filter 438, and a power amplifier module 440. The clockcircuit module includes a clock generator 444, a sample and hold (S&H)clock circuit 448, a filter clock circuit 446, a local oscillation (LO)clock circuit 450, and a digital to analog converter (DAC) clock circuit452.

In an example of operation, the DAC 432 receives an outbound symbolstream from the baseband processing module and converts it into ananalog signal. The up-conversion module 434 may be implemented usinganalog circuitry (e.g., a mixer, a local oscillation, and one or morepass filters) or it may be implemented as discrete time digitalcircuitry (e.g., a sample and hold circuit and a discrete time filter).Regardless of the implementation, the up-conversion module 434 convertsthe analog signal into an up-converted RF signal.

The sample and hold filter circuit 436 receives the up-converted RFsignal and samples it in accordance with a sample clock signal and ahold clock signal. With reference to FIG. 116, the sample and holdcircuit 436 receives the up-converted RF signal (G(f), which is shown inthe frequency domain) and samples it at a sampling frequency (fs). Inthis example, the sampling frequency is greater than or equal to twotimes the bandwidth of the up-converted RF signal. The sample and holdfilter 436 outputs, in the frequency domain, a plurality of pulsesspaced in frequency by the sampling frequency. The sample and holdoutput includes a pulse at RF, which corresponds to the originalup-converted RF signal.

Returning to the discussion of FIG. 115, the discrete time filter 438(which may be a finite impulse response filter, an infinite impulseresponse filter, a frequency translation bandpass filter, and/or othertype of discrete filter) receives the output of the sample and holdfilter circuit 436 and filters it at RF. For example and as shown inFIG. 117, the filtering response 454 of the discrete time filter 438corresponds to a bandpass filter centered at RF such that it outputs thepulse at RF and attenuates the pulses at the other frequencies toproduce an outbound RF signal.

The power amplifier 440, which includes one or more power amplifierscoupled in series and/or in parallel, outputs the outbound RF signal(s)to the antenna interface 442. Note that parameters (e.g., gain,linearity, bandwidth, efficiency, noise, output dynamic range, slewrate, rise rate, settling time, overshoot, stability factor, etc.) ofthe PA 440 may be adjusted based on control signals received from thebaseband processing module. For instance, as transmission conditionschange (e.g., channel response changes, distance between TX unit and RXunit changes, antenna properties change, etc.), the baseband processingmodule monitors the transmission condition changes and adjusts theproperties of the PA 440 to optimize performance.

FIG. 118 is a schematic block diagram of another embodiment of atransmitter of one or more of the transceivers of FIGS. 1-3 thatincludes a clock generation circuit 444, a digital to analog conversionmodule 432, a sample and hold filter circuit 436, a discrete time filter438, and a power amplifier module 440. The clock circuit module includesa clock generator 444, a sample and hold (S&H) clock circuit 448, afilter clock circuit 446, and a digital to analog converter (DAC) clockcircuit 452.

In an example of operation, the DAC 432 receives an outbound symbolstream from the baseband processing module and converts it into ananalog signal. The sample and hold filter circuit 448 receives theanalog signal and samples it in accordance with a sample clock signaland a hold clock signal. With reference to FIG. 119, the sample and holdcircuit 436 receives the baseband analog signal G(f), which is shown inthe frequency domain) and samples it at a sampling frequency (fs). Inthis example, the sampling frequency is greater than or equal to twotimes the bandwidth of the baseband signal and is an integer fraction ofthe desired RF (e.g., fs=RF/n, where n is an integer that is equal to orgreater than 2). The sample and hold filter 436 outputs, in thefrequency domain, a plurality of pulses spaced in frequency by thesampling frequency. The sample and hold output includes a pulse atbaseband, which corresponds to the original baseband signal, andincludes a pulse at RF.

Returning to the discussion of FIG. 118, the discrete time filter 438(which may be a finite impulse response filter, an infinite impulseresponse filter, a frequency translation bandpass filter, and/or othertype of discrete filter) receives the output of the sample and holdfilter circuit 436 and filters it at RF. For example and as shown inFIG. 120, the filtering response of the discrete time filter 438corresponds to a bandpass filter centered at RF such that it outputs thepulse at RF and attenuates the pulses at the other frequencies toproduce an outbound RF signal.

The power amplifier 440, which includes one or more power amplifierscoupled in series and/or in parallel, outputs the outbound RF signal(s)to the antenna interface 442. Note that parameters (e.g., gain,linearity, bandwidth, efficiency, noise, output dynamic range, slewrate, rise rate, settling time, overshoot, stability factor, etc.) ofthe PA 440 may be adjusted based on control signals received from thebaseband processing module.

FIG. 121 is a schematic block diagram of another embodiment of atransmitter of one or more of the transceivers of FIGS. 1-3 thatincludes a clock generation circuit 444, a digital to analog conversionmodule 432, a sample and hold filter circuit 436, an AC couplingcapacitor (C), and a power amplifier module 440. The clock circuitmodule includes a clock generator 444, a sample and hold (S&H) clockcircuit 448, and a digital to analog converter (DAC) clock circuit 452.

In an example of operation, the DAC 432 receives an outbound symbolstream from the baseband processing module and converts it into ananalog signal. The sample and hold filter circuit 436 receives theanalog signal and samples it in accordance with a sample clock signaland a hold clock signal. With reference to FIG. 122, the sample and holdcircuit 436 receives the baseband analog signal (G(f), which is shown inthe frequency domain) and samples it at a sampling frequency (fs). Inthis example, the sampling frequency is equal to desired RF (e.g.,fs=RF). The sample and hold filter 436 outputs, in the frequency domain,a plurality of pulses spaced in frequency by the sampling frequency. Thesample and hold output includes a pulse at baseband, which correspondsto the original baseband signal, and includes a pulse at RF.

Returning to the discussion of FIG. 121, the AC coupling capacitorblocks the baseband pulse and passes the other pulses, including thepulse at RF. The power amplifier 440, which includes one or more poweramplifiers coupled in series and/or in parallel, has a bandwidth that issubstantially less than 2*RF. As such, as the PA 440 outputs theoutbound RF signal (e.g., the pulse at RF) to the antenna interface 442,it attenuates the pulses at n*RF as shown in FIG. 123. Note thatparameters (e.g., gain, linearity, bandwidth, efficiency, noise, outputdynamic range, slew rate, rise rate, settling time, overshoot, stabilityfactor, etc.) of the PA 440 may be adjusted based on control signalsreceived from the baseband processing module.

FIG. 124 is a schematic block diagram of an embodiment of a multipleoutput transmitter of one or more of the transceivers of FIGS. 1-3 thatincludes a clock generation circuit 444, a plurality of digital toanalog conversion modules (two shown) 442, a sample and hold filtercircuit 436, a discrete time filter 438, and a plurality of poweramplifier modules 440. The clock circuit module includes a clockgenerator 444, a sample and hold (S&H) clock circuit 448, a filter clockcircuit 446, a local oscillation (LO) clock circuit, and a plurality ofdigital to analog converter (DAC) clock circuits 452.

In an example of MIMO operation, each of the DACs 432 receives anoutbound symbol stream from the baseband processing module and convertsit into an analog baseband signal. The sample and hold filter circuit436 receives the analog baseband signals from the DACs 432 and samplesthem in accordance with a sampling frequency. With reference to FIG.125, the sample and hold circuit 436 receives the analog basebandsignals (G1(f) and G2(f)) and samples each of them at a samplingfrequency (fs). In this example, the sampling frequency is at thedesired RF. Alternatively, the sampling frequency may be 2*bandwidth ofthe outbound signals. The sample and hold filter 436 outputs, in thefrequency domain for each analog baseband signal, a plurality of pulsesspaced in frequency by the sampling frequency. The sample and holdoutput includes a pulse at RF, which corresponds to the originalup-converted RF signal.

Returning to the discussion of FIG. 124, the discrete time filter 438(which may be one or more finite impulse response filters, one or moreinfinite impulse response filters, and/or one or more frequencytranslation bandpass filter) receives the first and second outputs ofthe sample and hold filter circuit 436 and filters them at RF. Forexample and as shown in FIG. 126, the filtering response 454 of thediscrete time filter 438 corresponds to a bandpass filter centered at RFsuch that it outputs the pulse at RF and attenuates the pulses at theother frequencies for each signal to produce a first outbound RF signaland second outbound RF signal.

Each of the power amplifiers 440, which includes one or more poweramplifiers coupled in series and/or in parallel, outputs a correspondingone of the outbound RF signals to a respective antenna interface 442.Note that parameters (e.g., gain, linearity, bandwidth, efficiency,noise, output dynamic range, slew rate, rise rate, settling time,overshoot, stability factor, etc.) of the PA 440 may be adjusted basedon control signals received from the baseband processing module.

In an example of multiple frequency band operation, each of the DACs 432receives an outbound symbol stream from the baseband processing moduleand converts it into an analog baseband signal. The sample and holdfilter circuit 436 receives the analog baseband signals from the DACsand samples them in accordance with a sampling frequency. With referenceto FIG. 127, the sample and hold circuit 448 receives the analogbaseband signals (G1(f) and G2(f)) and samples each of them at a firstsampling frequency (fs1) and a second sampling frequency (fs2),respectively. In this example, the first sampling frequency is at thefirst desired RF1 and the second sampling frequency is at the seconddesired RF2. Alternatively, the sampling frequency may be a function ofa bandwidth that spans the bandwidth of both outbound signals. Thesample and hold filter 436 outputs, in the frequency domain for eachanalog baseband signal, a plurality of pulses spaced in frequency by therespective sampling frequency. For each signal, the sample and holdoutput includes a pulse at RF (e.g., RF1 or RF2), which corresponds tothe original up-converted RF signal.

Returning to the discussion of FIG. 124, the discrete time filter 438(which may be one or more finite impulse response filters, one or moreinfinite impulse response filters, and/or one or more frequencytranslation bandpass filter) receives the first and second outputs ofthe sample and hold filter circuit 436 and filters them at RF. Forexample and as shown in FIG. 128, the filtering response 454 of thediscrete time filter 438 corresponds to a bandpass filter centered atRF1 and another centered at RF2 such that it outputs the pulse at RF1and attenuates the pulses at the other frequencies for the first signalto produce a first outbound RF signal and outputs the pulse at RF2 andattenuates the pulses at the other frequencies for the second signal toproduce a second outbound RF signal.

Each of the power amplifiers 440, which includes one or more poweramplifiers coupled in series and/or in parallel, outputs a correspondingone of the outbound RF signals to a respective antenna interface 442.Note that parameters (e.g., gain, linearity, bandwidth, efficiency,noise, output dynamic range, slew rate, rise rate, settling time,overshoot, stability factor, etc.) of the PA 440 may be adjusted basedon control signals received from the baseband processing module.

FIG. 129 is a schematic block diagram of another embodiment of atransceiver that includes a receiver section and a transmitter section.The receiver section includes a band pass filter (BPF), a low noiseamplifier (LNA) 456, a sample and hold filter circuit 458, a discretetime filter 460, an analog to digital converter (ADC) 462, and areceiver clock circuit module. The receiver clock circuit moduleincludes a clock generator 464, a sample and hold (S&H) clock circuit466, a filter clock circuit 468, and an analog to digital converter(ADC) clock circuit 470.

The transmitter section includes a transmit clock generation circuit444, a digital to analog conversion module 432, a sample and hold filtercircuit 436, a discrete time filter 438, and a power amplifier module440. The transmit clock circuit module includes a clock generator 444, asample and hold (S&H) clock circuit 448, a filter clock circuit 446, anda digital to analog converter (DAC) clock circuit 452. Note that anyother embodiment of the receiver section may be incorporated into thetransceiver with any other embodiment of the transmitter section.

In an example of operation, the processing module 472 generates controlsignals and/or settings 474 for the transmitter section and/or thereceiver section to improve transceiver performance, reduce transmitterinterference on the receiver side, etc. For example, the bandpassfiltering of the S&H circuits 436 and 458 may be adjusted to place nullsat interfering frequencies. As another example, the filter response ofthe frequency translation filter 460 (or discrete time filter 438) maybe tuned to provide a sharper attenuation, a different center frequency,etc. As yet another example, the clocking of the DAC 432 and ADC 462 maybe coordinated to reduce interference therebetween, noise injections,etc.

As may be used herein, the terms “substantially” and “approximately”provides an industry-accepted tolerance for its corresponding termand/or relativity between items. Such an industry-accepted toleranceranges from less than one percent to fifty percent and corresponds to,but is not limited to, component values, integrated circuit processvariations, temperature variations, rise and fall times, and/or thermalnoise. Such relativity between items ranges from a difference of a fewpercent to magnitude differences. As may also be used herein, theterm(s) “operably coupled to”, “coupled to”, and/or “coupling” includesdirect coupling between items and/or indirect coupling between items viaan intervening item (e.g., an item includes, but is not limited to, acomponent, an element, a circuit, and/or a module) where, for indirectcoupling, the intervening item does not modify the information of asignal but may adjust its current level, voltage level, and/or powerlevel. As may further be used herein, inferred coupling (i.e., where oneelement is coupled to another element by inference) includes direct andindirect coupling between two items in the same manner as “coupled to”.As may even further be used herein, the term “operable to” or “operablycoupled to” indicates that an item includes one or more of powerconnections, input(s), output(s), etc., to perform, when activated, oneor more its corresponding functions and may further include inferredcoupling to one or more other items. As may still further be usedherein, the term “associated with”, includes direct and/or indirectcoupling of separate items and/or one item being embedded within anotheritem. As may be used herein, the term “compares favorably”, indicatesthat a comparison between two or more items, signals, etc., provides adesired relationship. For example, when the desired relationship is thatsignal 1 has a greater magnitude than signal 2, a favorable comparisonmay be achieved when the magnitude of signal 1 is greater than that ofsignal 2 or when the magnitude of signal 2 is less than that of signal1.

As may also be used herein, the terms “processing module”, “module”,“processing circuit”, and/or “processing unit” may be a singleprocessing device or a plurality of processing devices. Such aprocessing device may be a microprocessor, micro-controller, digitalsignal processor, microcomputer, central processing unit, fieldprogrammable gate array, programmable logic device, state machine, logiccircuitry, analog circuitry, digital circuitry, and/or any device thatmanipulates signals (analog and/or digital) based on hard coding of thecircuitry and/or operational instructions. The processing module,module, processing circuit, and/or processing unit may have anassociated memory and/or an integrated memory element, which may be asingle memory device, a plurality of memory devices, and/or embeddedcircuitry of the processing module, module, processing circuit, and/orprocessing unit. Such a memory device may be a read-only memory, randomaccess memory, volatile memory, non-volatile memory, static memory,dynamic memory, flash memory, cache memory, and/or any device thatstores digital information. Note that if the processing module, module,processing circuit, and/or processing unit includes more than oneprocessing device, the processing devices may be centrally located(e.g., directly coupled together via a wired and/or wireless busstructure) or may be distributedly located (e.g., cloud computing viaindirect coupling via a local area network and/or a wide area network).Further note that if the processing module, module, processing circuit,and/or processing unit implements one or more of its functions via astate machine, analog circuitry, digital circuitry, and/or logiccircuitry, the memory and/or memory element storing the correspondingoperational instructions may be embedded within, or external to, thecircuitry comprising the state machine, analog circuitry, digitalcircuitry, and/or logic circuitry. Still further note that, the memoryelement may store, and the processing module, module, processingcircuit, and/or processing unit executes, hard coded and/or operationalinstructions corresponding to at least some of the steps and/orfunctions illustrated in one or more of the Figures. Such a memorydevice or memory element can be included in an article of manufacture.

The present invention has been described above with the aid of methodsteps illustrating the performance of specified functions andrelationships thereof. The boundaries and sequence of these functionalbuilding blocks and method steps have been arbitrarily defined hereinfor convenience of description. Alternate boundaries and sequences canbe defined so long as the specified functions and relationships areappropriately performed. Any such alternate boundaries or sequences arethus within the scope and spirit of the claimed invention. Further, theboundaries of these functional building blocks have been arbitrarilydefined for convenience of description. Alternate boundaries could bedefined as long as the certain significant functions are appropriatelyperformed. Similarly, flow diagram blocks may also have been arbitrarilydefined herein to illustrate certain significant functionality. To theextent used, the flow diagram block boundaries and sequence could havebeen defined otherwise and still perform the certain significantfunctionality. Such alternate definitions of both functional buildingblocks and flow diagram blocks and sequences are thus within the scopeand spirit of the claimed invention. One of average skill in the artwill also recognize that the functional building blocks, and otherillustrative blocks, modules and components herein, can be implementedas illustrated or by discrete components, application specificintegrated circuits, processors executing appropriate software and thelike or any combination thereof.

The present invention may have also been described, at least in part, interms of one or more embodiments. An embodiment of the present inventionis used herein to illustrate the present invention, an aspect thereof, afeature thereof, a concept thereof, and/or an example thereof. Aphysical embodiment of an apparatus, an article of manufacture, amachine, and/or of a process that embodies the present invention mayinclude one or more of the aspects, features, concepts, examples, etc.described with reference to one or more of the embodiments discussedherein. Further, from figure to figure, the embodiments may incorporatethe same or similarly named functions, steps, modules, etc. that may usethe same or different reference numbers and, as such, the functions,steps, modules, etc. may be the same or similar functions, steps,modules, etc. or different ones.

While the transistors in the above described figure(s) is/are shown asfield effect transistors (FETs), as one of ordinary skill in the artwill appreciate, the transistors may be implemented using any type oftransistor structure including, but not limited to, bipolar, metal oxidesemiconductor field effect transistors (MOSFET), N-well transistors,P-well transistors, enhancement mode, depletion mode, and zero voltagethreshold (VT) transistors.

Unless specifically stated to the contra, signals to, from, and/orbetween elements in a figure of any of the figures presented herein maybe analog or digital, continuous time or discrete time, and single-endedor differential. For instance, if a signal path is shown as asingle-ended path, it also represents a differential signal path.Similarly, if a signal path is shown as a differential path, it alsorepresents a single-ended signal path. While one or more particulararchitectures are described herein, other architectures can likewise beimplemented that use one or more data buses not expressly shown, directconnectivity between elements, and/or indirect coupling between otherelements as recognized by one of average skill in the art.

The term “module” is used in the description of the various embodimentsof the present invention. A module includes a functional block that isimplemented via hardware to perform one or module functions such as theprocessing of one or more input signals to produce one or more outputsignals. The hardware that implements the module may itself operate inconjunction software, and/or firmware. As used herein, a module maycontain one or more sub-modules that themselves are modules.

While particular combinations of various functions and features of thepresent invention have been expressly described herein, othercombinations of these features and functions are likewise possible. Thepresent invention is not limited by the particular examples disclosedherein and expressly incorporates these other combinations.

1. A receiver comprises: a sample and hold module including: a sampleswitching module operable, in accordance with a sampling clock signal,to output samples of an inbound wireless signal; an impedance moduleoperably coupled to temporarily store the samples of the inboundwireless signal to produce a plurality of samples; and a hold switchingmodule operable, in accordance with a hold clock signal, to output afiltered representation of the plurality of samples to produce afrequency domain sample pulse train, wherein a filter response of thesample and hold module is in accordance with a ratio between thesampling clock signal and the hold clock signal; a discrete time filtermodule operable to filter the frequency domain sample pulse train toproduce a filtered sample pulse; and a conversion module operable toconvert the filtered sample pulse into an inbound baseband signal. 2.The receiver of claim 1 further comprises: a sample and hold clockmodule operable to: generate the sampling clock signal in accordancewith the sample and hold clock control signal; and generate the holdclock signal in accordance with the sample and hold clock controlsignal; and a processing module operable to generate the sample and holdclock control signal to facilitate establishing the filter response ofthe sample and hold module.
 3. The receiver of claim 1 furthercomprises: a bandpass filter module operable to filter the inboundwireless signal, wherein the sample clock signal and the hold clocksignal are at a rate corresponding to a multiple of bandwidth of theinbound wireless signal.
 4. The receiver of claim 1, wherein theimpedance module comprises one or more of: a capacitor; acapacitor-inductor circuit; and an active element capacitor-inductorcircuit.
 5. The receiver of claim 1 further comprises: a processingmodule operably coupled to generate a tuning control signal tofacilitate establishing the filter response of the sample and holdmodule, wherein a frequency response of the impedance module is tuned inaccordance with the tuning control signal such that the impedance modulestores a tuned representation of the samples of the inbound wirelesssignal as the plurality of samples.
 6. The receiver of claim 1, whereinthe sample and hold module further comprises: a plurality of sampleswitching modules, wherein: the sample switching module of the pluralitysample switching modules is operable, in accordance with the samplingclock signal, to output samples of the inbound wireless signal; and asecond sample switching module of the plurality sample switching modulesis operable, in accordance with a second sampling clock signal, tooutput samples of a second inbound wireless signal; the impedance moduleoperably coupled to: temporarily store the samples of the inboundwireless signal to produce the plurality of samples; and temporarilystore the samples of the second inbound wireless signal to produce asecond plurality of samples; and a plurality of hold switching modules,wherein: the hold switching module of the plurality of hold modules isoperable, in accordance with the hold clock signal, to output thefiltered representation of the plurality of samples; and a second holdswitching module of the plurality of hold modules is operable, inaccordance with a second hold clock signal, to output a filteredrepresentation of the second plurality of samples to produce a secondfrequency domain sample pulse train, wherein a second filter response ofthe sample and hold module is in accordance with a ratio between thesecond sampling clock signal and the second hold clock signal.
 7. Thereceiver of claim 1, wherein the conversion module comprises at leastone of: a wireless frequency to baseband conversion module to convertthe filtered sample pulse to a baseband digital signal; and an analog todigital conversion module operable to convert the baseband digitalsignal or the filtered sample pulse into the inbound baseband signal. 8.The receiver of claim 1, wherein the sample and hold module furthercomprises: a hold impedance module operably coupled to temporarily storethe frequency domain sample pulse train.
 9. A receiver comprises: asample and hold module operable to sample and hold, at a ratecorresponding to a multiple of a frequency-dependent component of aninbound wireless signal, the inbound wireless signal to produce afrequency domain sample pulse train; a programmable discrete time filtermodule operable to: generate a control information in accordance with adesired bandpass filter response; establish one or more of bandpassregion, gain, center frequency, roll-off, and quality factor inaccordance with the control information to produce a bandpass filterresponse; filter, in accordance with the bandpass filter response, thefrequency domain sample pulse train to produce a filtered sample pulse;and a conversion module operable to convert the filtered sample pulseinto an inbound baseband signal.
 10. The receiver of claim 9, whereinthe programmable discrete time filter module comprises: a programmablefinite impulse response filter that includes: a programmable delay lineoperable to input the frequency domain sample pulse train, where delayof delay elements of the programmable delay line is established inaccordance with the control information; a plurality of stages coupledto the programmable delay line, wherein a stage of the plurality ofstages includes a summing module and a coefficient register for storinga coefficient, wherein the coefficient is set in accordance with thecontrol information; and an output module operable to combine selectedoutputs of the plurality of stages in accordance with the controlinformation to produce the filtered sample pulse.
 11. The receiver ofclaim 9, wherein the programmable discrete time filter module comprises:a programmable infinite impulse response filter that includes: a firstprogrammable delay line operable to input the frequency domain samplepulse train, where delay of delay elements of the first programmabledelay line is established in accordance with the control information; afirst plurality of stages coupled to the first programmable delay line,wherein a stage of the first plurality of stages includes a firstsumming module and a first coefficient register for storing a firstcoefficient, wherein the first coefficient is set in accordance with thecontrol information; a second programmable delay line operable to inputthe filtered sample pulse, where delay of delay elements of the secondprogrammable delay line is established in accordance with the controlinformation; a second plurality of stages coupled to the secondprogrammable delay line, wherein a stage of the second plurality ofstages includes a second summing module and a second coefficientregister for storing a second coefficient, wherein the secondcoefficient is set in accordance with the control information; and anoutput module operable to combine selected outputs of the first andsecond plurality of stages in accordance with the control information toproduce the filtered sample pulse.
 12. The receiver of claim 9, whereinthe programmable discrete time filter module comprises: a programmablefrequency translation bandpass filter that includes: a plurality ofswitching elements; a plurality of baseband impedances connected to theplurality of switching elements that collectively form a basebandfilter; and a programmable filter clock circuit operable to generate aplurality of phase-shifted clock signals in accordance with the controlinformation, wherein the plurality of switching elements are clocked viathe plurality of phase-shifted clock signals such that the basebandfilter is frequency translated to a wireless frequency bandpass filter.13. The receiver of claim 12, wherein the plurality of basebandimpedances comprises: a plurality of programmable impedances that isprogrammed in accordance with the control information to establish adesired frequency response of the baseband filter.
 14. The receiver ofclaim 9, wherein the frequency-dependent component of the inboundwireless signal comprises at least one of: bandwidth of the inboundwireless signal; and a carrier frequency of the inbound wireless signal.15. A receiver comprises: a sample and hold module operable to sampleand hold, at a rate corresponding to a multiple of a frequency-dependentcomponent of an inbound wireless signal, the inbound wireless signal toproduce a frequency domain sample pulse train; a discrete time filtermodule operable to filter the frequency domain sample pulse train toproduce a filtered sample pulse; and a programmable conversion modulethat includes: a second sample and hold module operable to sample andhold, at a rate established based on control information, the filteredsample pulse to produce a second frequency domain sample pulse train; asecond discrete time filter module operable to filter the secondfrequency domain sample pulse train to produce a baseband sample pulse;and an analog to digital converter operable to convert the basebandsample pulse into an inbound baseband signal.
 16. The receiver of claim15, wherein the second discrete time filter comprises at least one of: aprogrammable finite impulse response filter; a programmable infiniteimpulse response filter; and a programmable frequency translationbandpass filter.
 17. The receiver of claim 15 further comprises: aprocessing module operable to generate the control information, wherein,when the frequency-dependent component of the inbound wireless signalcorresponds to a carrier frequency of the inbound wireless signal, theprocessing module generates the control information such that the ratefor sampling and holding by the second sample and hold modulecorresponds to a bandwidth of the inbound wireless signal.
 18. Thereceiver of claim 15 further comprises: a processing module operable togenerate the control information, wherein, when the frequency-dependentcomponent of the inbound wireless signal corresponds to the bandwidth ofthe inbound wireless signal, the processing module generates the controlinformation such that the discrete time filter module filters, inaccordance with the control information, the frequency domain samplepulse train to produce an intermediate frequency (IF) filtered samplepulse and such that the rate for sampling and holding by the secondsample and hold module corresponds to a frequency component of the IFfiltered sample pulse.
 19. The receiver of claim 15, wherein the secondsample and hold circuit comprises: a sample switching module operable,in accordance with a sampling clock signal, to output samples of thefiltered sample pulse; an impedance module operably coupled totemporarily store the samples of the filtered sampled pulse to produce aplurality of samples; and a hold switching module operable, inaccordance with a hold clock signal, to output a filtered representationof the plurality of samples to produce the second frequency domainsample pulse train, wherein a filter response of the sample and holdmodule is in accordance with a ratio between the sampling clock signaland the hold clock signal.